Fork WebSocket

For the complete documentation index, see llms.txt. Markdown versions of documentation pages are available by appending .md to the page URL.

Start a new Live session from stored conversation state. Send and receive audio and control events on the new WebSocket connection.

WS /v1/live/sessions/{session_id}/fork

Connection

wss://api.openai.com/v1/live/sessions/{session_id}/fork

Authenticate from your backend with your OpenAI API key in the Authorization: Bearer $OPENAI_API_KEY header. Keep the key on your server.

session_id (required path parameter): The ID of the stored source session to fork. The fork receives a new session ID.

No query parameters. After connecting, send session.start with a session overrides object. An empty object inherits the stored configuration. Do not supply a new model. Wait for session.started before sending audio or other commands.

Inputs

Required once after connecting. Omitted settings are inherited, including store. You may override Responses delegation settings, storage, and the new WebSocket audio format. Frontend client permissions apply only to WebRTC forks.

First message: session.start

{
  "type": "session.start",
  "session": {}
}

All client events

Outputs

The server confirms the new session is ready. Use its new ID for subsequent sideband connections and session controls.

Fork ready · excerpt: session.started

{
  "type": "session.started",
  "event_id": "event_started_1",
  "session": {
    "id": "live_fork_123",
    "expires_at": 1788307200,
    "status": "active",
    "model": "gpt-live-1"
  }
}

All server events

Learn how to store a session and fork its conversation.

Client events

session.start

Start a Live session after connecting to a stored session’s fork WebSocket. Send an empty session object to use the stored configuration.

Schema

Schema name: LiveForkSessionStartEvent

• session: ForkSessionConfig

  Overrides for a stored session after connecting to the fork WebSocket. An empty object inherits the stored configuration; do not supply a new model. audio.format applies only to the new WebSocket connection. client overrides are only supported for WebRTC forks.

  • audio: optional object { format }

    Audio format for a WebSocket fork. WebRTC forks negotiate their audio format and must omit this field.

    • format: optional AudioFormat

      Audio encoding and sample rate for audio sent and received over a Live WebSocket connection. WebRTC and SIP negotiate their media format separately.

      • AudioPCM object { rate, type }

        Raw, mono 16-bit little-endian PCM audio for a Live WebSocket connection.

        • rate: 16000 or 24000

          Audio sample rate in hertz. Live WebSocket PCM audio supports 16000 or 24000 Hz.

          • 16000

          • 24000

        • type: "audio/pcm"

          The audio encoding. Always audio/pcm.

          • "audio/pcm"

      • AudioPCMU object { rate, type }

        Raw, mono G.711 μ-law audio for a Live WebSocket connection.

        • rate: number

          Audio sample rate in hertz. G.711 audio uses 8000 Hz.

        • type: "audio/pcmu"

          The audio encoding. Always audio/pcmu.

          • "audio/pcmu"

      • AudioPCMA object { rate, type }

        Raw, mono G.711 A-law audio for a Live WebSocket connection.

        • rate: number

          Audio sample rate in hertz. G.711 audio uses 8000 Hz.

        • type: "audio/pcma"

          The audio encoding. Always audio/pcma.

          • "audio/pcma"

  • client: optional ClientConfig

    Frontend data-channel permissions for a WebRTC fork. Omitted permissions inherit the stored values. Not supported for WebSocket forks.

    • data_channel: DataChannelConfig

      Client and server event permissions for the WebRTC frontend data channel.

      • allowed_client_events: optional "all" or array of string

        Client event types that the frontend data channel may send. Use 'all' to allow every client event; an empty array allows none. Omission preserves the existing allow-all behavior.

        • "all"

          • "all"

        • array of string

      • allowed_server_events: optional "all" or array of ServerEventSelector

        Server events that may be sent to the frontend data channel. Use 'all' to allow every server event; an empty array allows none. Omission preserves the existing allow-all behavior. Responses events use an object with type 'response.event' and a response_event selector.

        • "all"

          • "all"

        • array of ServerEventSelector

          • type: string

            The outer Live server event type. Use 'response.event' for Responses events.

          • response_event: optional string

            The nested Responses event type. Required when type is 'response.event'; forbidden for other event types.

  • delegation: optional object { type, responses }

    Overrides for the stored session’s Responses backend. Only supported when the stored session already uses Responses delegation; the delegation type cannot change.

    • type: "responses"

      The delegation owner. Always responses for tasks handled by the Responses API.

      • "responses"

    • responses: optional ResponsesDelegationUpdateConfig

      Responses backend settings to update. Omitted settings keep their existing values.

      • instructions: optional string or null

        Instructions for the delegated Responses model, separate from Live instructions. See backend prompting.

      • max_output_tokens: optional number or null

        Maximum number of output tokens for each delegated response.

      • model: optional string

        The Responses backend model to use for subsequent delegated requests. Omit to keep the current backend model.

      • parallel_tool_calls: optional boolean or null

        Whether the delegated Responses model may request multiple tool calls in a single response.

      • reasoning: optional object { effort, summary } or null

        Reasoning settings passed to each delegated Responses request.

        • effort: optional "none" or "minimal" or "low" or 3 more or null

          How much reasoning effort the delegated Responses model should use. Supported values depend on the backend model.

          • "none"

          • "minimal"

          • "low"

          • "medium"

          • "high"

          • "xhigh"

        • summary: optional "concise" or "detailed" or "auto" or null

          The reasoning summary to request from the delegated Responses model, when supported.

          • "concise"

          • "detailed"

          • "auto"

      • service_tier: optional "auto" or "default" or "fast_tier_temp_pilot" or 3 more or null

        Service tier for delegated Responses requests.

        • "auto"

        • "default"

        • "fast_tier_temp_pilot"

        • "flex"

        • "priority"

        • "ultrafast"

      • text: optional object { verbosity } or null

        Text generation settings passed to each delegated Responses request.

        • verbosity: optional "low" or "medium" or "high" or null

          The amount of detail in text generated by the Responses backend. This does not configure the Live model’s spoken delivery.

          • "low"

          • "medium"

          • "high"

      • tool_choice: optional "auto" or "none" or "required" or object { name, type } or object { name, server_label, type }

        Controls which tool the Responses backend uses when handling a task delegated by the Live model.

        • LiveToolChoiceEnum = "auto" or "none" or "required"

          • "auto"

          • "none"

          • "required"

        • LiveFunctionToolChoiceParam object { name, type }

          • name: string

          • type: "function"

            • "function"

        • LiveMCPToolChoiceParam object { name, server_label, type }

          • name: string

          • server_label: string

          • type: "mcp"

            • "mcp"

      • tools: optional array of FunctionTool or object { type }

        Tools available to the Responses backend while it handles tasks delegated by the Live model.

        • FunctionTool object { name, type, description, 2 more }

          A function tool available to the Responses backend when the Live model delegates a task.

          • name: string

            The name the delegated Responses model uses when calling this function.

          • type: "function"

            The tool type. Always function.

            • "function"

          • description: optional string or null

            What the function does and when the delegated Responses model should call it.

          • parameters: optional map[unknown] or null

            A JSON Schema object describing the arguments accepted by the function.

          • strict: optional boolean or null

            Whether the delegated Responses model must follow the function’s parameter schema exactly.

        • WebSearch object { type }

          A web search tool available to the Live session’s Responses backend.

          • type: "web_search"

            The tool type. Always web_search.

            • "web_search"

  • store: optional boolean

    Whether to store the forked session. Omission inherits the stored session's setting.

• type: "session.start"

  The Live client event type. Always session.start.

  • "session.start"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.start",
  "session": {}
}

session.update

Update the delegation settings of an active Live session. The server acknowledges accepted changes with session.updated.

Schema

Schema name: LiveSessionUpdateParam

• session: SessionUpdateConfig

  Sparse delegation updates. Omitted settings retain their values. The delegation type cannot change, including resetting Responses delegation to null or client. Model, frontend instructions, audio, and startup input are immutable.

  • delegation: optional ClientDelegation or object { type, responses } or null

    Delegation settings to update. The delegation type must match the current session; omitted settings retain their values.

    • ClientDelegation object { type }

      Delegate tasks to your application. The Live session emits delegation events that your backend handles.

      • type: "client"

        The delegation owner. Always client for tasks handled by your application.

        • "client"

    • Responses object { type, responses }

      Update the Responses backend for an existing Live session without changing delegation ownership.

      • type: "responses"

        The delegation owner. Always responses for tasks handled by the Responses API.

        • "responses"

      • responses: optional ResponsesDelegationUpdateConfig

        Responses backend settings to update. Omitted settings keep their existing values.

        • instructions: optional string or null

          Instructions for the delegated Responses model, separate from Live instructions. See backend prompting.

        • max_output_tokens: optional number or null

          Maximum number of output tokens for each delegated response.

        • model: optional string

          The Responses backend model to use for subsequent delegated requests. Omit to keep the current backend model.

        • parallel_tool_calls: optional boolean or null

          Whether the delegated Responses model may request multiple tool calls in a single response.

        • reasoning: optional object { effort, summary } or null

          Reasoning settings passed to each delegated Responses request.

          • effort: optional "none" or "minimal" or "low" or 3 more or null

            How much reasoning effort the delegated Responses model should use. Supported values depend on the backend model.

            • "none"

            • "minimal"

            • "low"

            • "medium"

            • "high"

            • "xhigh"

          • summary: optional "concise" or "detailed" or "auto" or null

            The reasoning summary to request from the delegated Responses model, when supported.

            • "concise"

            • "detailed"

            • "auto"

        • service_tier: optional "auto" or "default" or "fast_tier_temp_pilot" or 3 more or null

          Service tier for delegated Responses requests.

          • "auto"

          • "default"

          • "fast_tier_temp_pilot"

          • "flex"

          • "priority"

          • "ultrafast"

        • text: optional object { verbosity } or null

          Text generation settings passed to each delegated Responses request.

          • verbosity: optional "low" or "medium" or "high" or null

            The amount of detail in text generated by the Responses backend. This does not configure the Live model’s spoken delivery.

            • "low"

            • "medium"

            • "high"

        • tool_choice: optional "auto" or "none" or "required" or object { name, type } or object { name, server_label, type }

          Controls which tool the Responses backend uses when handling a task delegated by the Live model.

          • LiveToolChoiceEnum = "auto" or "none" or "required"

            • "auto"

            • "none"

            • "required"

          • LiveFunctionToolChoiceParam object { name, type }

            • name: string

            • type: "function"

              • "function"

          • LiveMCPToolChoiceParam object { name, server_label, type }

            • name: string

            • server_label: string

            • type: "mcp"

              • "mcp"

        • tools: optional array of FunctionTool or object { type }

          Tools available to the Responses backend while it handles tasks delegated by the Live model.

          • FunctionTool object { name, type, description, 2 more }

            A function tool available to the Responses backend when the Live model delegates a task.

            • name: string

              The name the delegated Responses model uses when calling this function.

            • type: "function"

              The tool type. Always function.

              • "function"

            • description: optional string or null

              What the function does and when the delegated Responses model should call it.

            • parameters: optional map[unknown] or null

              A JSON Schema object describing the arguments accepted by the function.

            • strict: optional boolean or null

              Whether the delegated Responses model must follow the function’s parameter schema exactly.

          • WebSearch object { type }

            A web search tool available to the Live session’s Responses backend.

            • type: "web_search"

              The tool type. Always web_search.

              • "web_search"

• type: "session.update"

  The Live client event type. Always session.update.

  • "session.update"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.update",
  "event_id": "evt_update_001",
  "session": {
    "delegation": {
      "type": "responses",
      "responses": {
        "instructions": "Check restaurant availability. Ask before confirming a booking.",
        "max_output_tokens": 1024
      }
    }
  }
}

session.input_audio.append

Send audio to a Live session over its primary WebSocket. WebRTC and SIP sessions send audio over their media transport.

Schema

Schema name: LiveInputAudioAppendEvent

• audio: string

  Base64-encoded raw audio in the startup-selected format, without a WAV or other container header. Primary WebSocket only; media transports use their audio track. Audio appends have no acknowledgment. Reflected sideband server events reuse this event type and audio key, with no timestamps or event_id; their audio is always mono PCM16LE at 24 kHz.

• type: "session.input_audio.append"

  The Live client event type. Always session.input_audio.append.

  • "session.input_audio.append"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.input_audio.append",
  "audio": "AACAAIAAAIAAAP9/AIAAgA=="
}

session.input_audio.mute

Mute audio input to the Live model without closing the session. The server acknowledges with session.input_audio.muted.

Schema

Schema name: LiveInputAudioMuteParam

• type: "session.input_audio.mute"

  The Live client event type. Always session.input_audio.mute.

  • "session.input_audio.mute"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.input_audio.mute",
  "event_id": "evt_mute_001"
}

session.input_audio.unmute

Resume audio input to a Live model after muting it. The server acknowledges with session.input_audio.unmuted.

Schema

Schema name: LiveInputAudioUnmuteParam

• type: "session.input_audio.unmute"

  The Live client event type. Always session.input_audio.unmute.

  • "session.input_audio.unmute"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.input_audio.unmute",
  "event_id": "evt_unmute_001"
}

session.instructions.append

Append instructions to the Live conversation while it is running, optionally associating them with an existing client delegation.

Schema

Schema name: LiveInstructionsAppendParam

• content: string

  Instruction text to append, limited to 500 tokens. This is a plain string, not an array of content parts.

• delegation_id: string or null

  Required, nullable. Set null for general session context, or use the ID from session.delegation.created for an existing client delegation. Non-null IDs are not accepted with Responses delegation.

• type: "session.instructions.append"

  The Live client event type. Always session.instructions.append.

  • "session.instructions.append"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.instructions.append",
  "event_id": "evt_instructions_001",
  "delegation_id": null,
  "content": "The caller prefers outdoor seating."
}

session.thinking.append

Provide silent reasoning or progress context to the Live model, optionally for an existing client delegation.

Schema

Schema name: LiveThinkingAppendParam

• content: string

  Silent reasoning or progress context, limited to 500 tokens. It does not directly request speech, but can influence later speech and is not a secrecy boundary.

• delegation_id: string or null

  Required, nullable. Set null for general session context, or use the ID from session.delegation.created for an existing client delegation. Non-null IDs are not accepted with Responses delegation.

• type: "session.thinking.append"

  The Live client event type. Always session.thinking.append.

  • "session.thinking.append"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.thinking.append",
  "event_id": "evt_thinking_001",
  "delegation_id": "del_abc123",
  "content": "Checking availability for two guests at 7 PM."
}

session.commentary.append

Provide context the Live model can communicate to the user, optionally for an existing client delegation.

Schema

Schema name: LiveCommentaryAppendParam

• content: string

  Speakable context for the Live model, limited to 500 tokens. Use this for a result the model should communicate; use session.thinking.append for silent context.

• delegation_id: string or null

  Required, nullable. Set null for general session context, or use the ID from session.delegation.created for an existing client delegation. Non-null IDs are not accepted with Responses delegation.

• type: "session.commentary.append"

  The Live client event type. Always session.commentary.append.

  • "session.commentary.append"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.commentary.append",
  "event_id": "evt_commentary_001",
  "delegation_id": "del_abc123",
  "content": "There is an outdoor table for two at 7 PM. Ask whether to reserve it."
}

response.item.create

Add an input item to the Live session’s Responses backend. Requires Responses delegation; use response.create to request a response.

Schema

Schema name: LiveResponseItemCreateParam

• item: EasyInputMessage or object { content, role, status, type } or ResponseOutputMessage or 30 more

  An input item to append to the Responses backend conversation, such as a user message or a function tool result.

  • EasyInputMessage object { content, role, phase, type }

    A message input to the model with a role indicating instruction following hierarchy. Instructions given with the developer or system role take precedence over instructions given with the user role. Messages with the assistant role are presumed to have been generated by the model in previous interactions.

    • content: string or ResponseInputMessageContentList

      Text, image, or audio input to the model, used to generate a response. Can also contain previous assistant responses.

      • TextInput = string

        A text input to the model.

      • ResponseInputMessageContentList = array of ResponseInputContent

        A list of one or many input items to the model, containing different content types.

        • ResponseInputText object { text, type, prompt_cache_breakpoint }

          A text input to the model.

          • text: string

            The text input to the model.

          • type: "input_text"

            The type of the input item. Always input_text.

            • "input_text"

          • prompt_cache_breakpoint: optional object { mode }

            Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request's prompt_cache_options.ttl; the boundary is not rounded to a token block.

            • mode: "explicit"

              The breakpoint mode. Always explicit.

              • "explicit"

        • ResponseInputImage object { detail, type, file_id, 2 more }

          An image input to the model. Learn about image inputs.

          • detail: ImageDetail

            The detail level of the image to be sent to the model. One of high, low, auto, or original. Defaults to auto.

            • "low"

            • "high"

            • "auto"

            • "original"

          • type: "input_image"

            The type of the input item. Always input_image.

            • "input_image"

          • file_id: optional string or null

            The ID of the file to be sent to the model.

          • image_url: optional string or null

            The URL of the image to be sent to the model. A fully qualified URL or base64 encoded image in a data URL.

          • prompt_cache_breakpoint: optional object { mode }

            Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request's prompt_cache_options.ttl; the boundary is not rounded to a token block.

            • mode: "explicit"

              The breakpoint mode. Always explicit.

              • "explicit"

        • ResponseInputFile object { type, detail, file_data, 4 more }

          A file input to the model.

          • type: "input_file"

            The type of the input item. Always input_file.

            • "input_file"

          • detail: optional "auto" or "low" or "high"

            The detail level of the file to be sent to the model. Use auto to let the system select the detail level; for GPT-5.6 and later models, auto uses high-quality rendering, which may increase input token usage. Use low for lower-cost rendering, or high to render the file at higher quality. Defaults to auto.

            • "auto"

            • "low"

            • "high"

          • file_data: optional string

            The content of the file to be sent to the model.

          • file_id: optional string or null

            The ID of the file to be sent to the model.

          • file_url: optional string

            The URL of the file to be sent to the model.

          • filename: optional string

            The name of the file to be sent to the model.

          • prompt_cache_breakpoint: optional object { mode }

            Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request's prompt_cache_options.ttl; the boundary is not rounded to a token block.

            • mode: "explicit"

              The breakpoint mode. Always explicit.

              • "explicit"

    • role: "user" or "assistant" or "system" or "developer"

      The role of the message input. One of user, assistant, system, or developer.

      • "user"

      • "assistant"

      • "system"

      • "developer"

    • phase: optional "commentary" or "final_answer" or null

      Labels an assistant message as intermediate commentary (commentary) or the final answer (final_answer). For models like gpt-5.3-codex and beyond, when sending follow-up requests, preserve and resend phase on all assistant messages — dropping it can degrade performance. Not used for user messages.

      • "commentary"

      • "final_answer"

    • type: optional "message"

      The type of the message input. Always message.

      • "message"

  • Message object { content, role, status, type }

    A message input to the model with a role indicating instruction following hierarchy. Instructions given with the developer or system role take precedence over instructions given with the user role.

    • content: ResponseInputMessageContentList

      A list of one or many input items to the model, containing different content types.

    • role: "user" or "system" or "developer"

      The role of the message input. One of user, system, or developer.

      • "user"

      • "system"

      • "developer"

    • status: optional "in_progress" or "completed" or "incomplete"

      The status of item. One of in_progress, completed, or incomplete. Populated when items are returned via API.

      • "in_progress"

      • "completed"

      • "incomplete"

    • type: optional "message"

      The type of the message input. Always set to message.

      • "message"

  • ResponseOutputMessage object { id, content, role, 3 more }

    An output message from the model.

    • id: string

      The unique ID of the output message.

    • content: array of ResponseOutputText or ResponseOutputRefusal

      The content of the output message.

      • ResponseOutputText object { annotations, logprobs, text, type }

        A text output from the model.

        • annotations: array of object { file_id, filename, index, type } or object { end_index, start_index, title, 2 more } or object { container_id, end_index, file_id, 3 more } or object { file_id, index, type }

          The annotations of the text output.

          • FileCitation object { file_id, filename, index, type }

            A citation to a file.

            • file_id: string

              The ID of the file.

            • filename: string

              The filename of the file cited.

            • index: number

              The index in the output text at which to insert the file citation.

            • type: "file_citation"

              The type of the file citation. Always file_citation.

              • "file_citation"

          • URLCitation object { end_index, start_index, title, 2 more }

            A citation for a web resource used to generate a model response.

            • end_index: number

              The index of the last character of the URL citation in the message.

            • start_index: number

              The index of the first character of the URL citation in the message.

            • title: string

              The title of the web resource.

            • type: "url_citation"

              The type of the URL citation. Always url_citation.

              • "url_citation"

            • url: string

              The URL of the web resource.

          • ContainerFileCitation object { container_id, end_index, file_id, 3 more }

            A citation for a container file used to generate a model response.

            • container_id: string

              The ID of the container file.

            • end_index: number

              The index of the last character of the container file citation in the message.

            • file_id: string

              The ID of the file.

            • filename: string

              The filename of the container file cited.

            • start_index: number

              The index of the first character of the container file citation in the message.

            • type: "container_file_citation"

              The type of the container file citation. Always container_file_citation.

              • "container_file_citation"

          • FilePath object { file_id, index, type }

            A path to a file.

            • file_id: string

              The ID of the file.

            • index: number

              The index of the file in the list of files.

            • type: "file_path"

              The type of the file path. Always file_path.

              • "file_path"

        • logprobs: array of object { token, bytes, logprob, top_logprobs }

          • token: string

          • bytes: array of number

          • logprob: number

          • top_logprobs: array of object { token, bytes, logprob }

            • token: string

            • bytes: array of number

            • logprob: number

        • text: string

          The text output from the model.

        • type: "output_text"

          The type of the output text. Always output_text.

          • "output_text"

      • ResponseOutputRefusal object { refusal, type }

        A refusal from the model.

        • refusal: string

          The refusal explanation from the model.

        • type: "refusal"

          The type of the refusal. Always refusal.

          • "refusal"

    • role: "assistant"

      The role of the output message. Always assistant.

      • "assistant"

    • status: "in_progress" or "completed" or "incomplete"

      The status of the message input. One of in_progress, completed, or incomplete. Populated when input items are returned via API.

      • "in_progress"

      • "completed"

      • "incomplete"

    • type: "message"

      The type of the output message. Always message.

      • "message"

    • phase: optional "commentary" or "final_answer" or null

      Labels an assistant message as intermediate commentary (commentary) or the final answer (final_answer). For models like gpt-5.3-codex and beyond, when sending follow-up requests, preserve and resend phase on all assistant messages — dropping it can degrade performance. Not used for user messages.

      • "commentary"

      • "final_answer"

  • FileSearchCall object { id, queries, status, 2 more }

    The results of a file search tool call. See the file search guide for more information.

    • id: string

      The unique ID of the file search tool call.

    • queries: array of string

      The queries used to search for files.

    • status: "in_progress" or "searching" or "completed" or 2 more

      The status of the file search tool call. One of in_progress, searching, incomplete or failed,

      • "in_progress"

      • "searching"

      • "completed"

      • "incomplete"

      • "failed"

    • type: "file_search_call"

      The type of the file search tool call. Always file_search_call.

      • "file_search_call"

    • results: optional array of object { attributes, file_id, filename, 2 more } or null

      The results of the file search tool call.

      • attributes: optional map[string or number or boolean] or null

        Set of 16 key-value pairs that can be attached to an object. This can be useful for storing additional information about the object in a structured format, and querying for objects via API or the dashboard. Keys are strings with a maximum length of 64 characters. Values are strings with a maximum length of 512 characters, booleans, or numbers.

        • string

        • number

        • boolean

      • file_id: optional string

        The unique ID of the file.

      • filename: optional string

        The name of the file.

      • score: optional number

        The relevance score of the file - a value between 0 and 1.

      • text: optional string

        The text that was retrieved from the file.

  • ComputerCall object { id, call_id, pending_safety_checks, 4 more }

    A tool call to a computer use tool. See the computer use guide for more information.

    • id: string

      The unique ID of the computer call.

    • call_id: string

      An identifier used when responding to the tool call with output.

    • pending_safety_checks: array of object { id, code, message }

      The pending safety checks for the computer call.

      • id: string

        The ID of the pending safety check.

      • code: optional string or null

        The type of the pending safety check.

      • message: optional string or null

        Details about the pending safety check.

    • status: "in_progress" or "completed" or "incomplete"

      The status of the item. One of in_progress, completed, or incomplete. Populated when items are returned via API.

      • "in_progress"

      • "completed"

      • "incomplete"

    • type: "computer_call"

      The type of the computer call. Always computer_call.

      • "computer_call"

    • action: optional ComputerAction

      A click action.

      • Click object { button, type, x, 2 more }

        A click action.

        • button: "left" or "right" or "wheel" or 2 more

          Indicates which mouse button was pressed during the click. One of left, right, wheel, back, or forward.

          • "left"

          • "right"

          • "wheel"

          • "back"

          • "forward"

        • type: "click"

          Specifies the event type. For a click action, this property is always click.

          • "click"

        • x: number

          The x-coordinate where the click occurred.

        • y: number

          The y-coordinate where the click occurred.

        • keys: optional array of string or null

          The keys being held while clicking.

      • DoubleClick object { keys, type, x, y }

        A double click action.

        • keys: array of string or null

          The keys being held while double-clicking.

        • type: "double_click"

          Specifies the event type. For a double click action, this property is always set to double_click.

          • "double_click"

        • x: number

          The x-coordinate where the double click occurred.

        • y: number

          The y-coordinate where the double click occurred.

      • Drag object { path, type, keys }

        A drag action.

        • path: array of object { x, y }

          An array of coordinates representing the path of the drag action. Coordinates will appear as an array of objects, eg

          [
            { x: 100, y: 200 },
            { x: 200, y: 300 }
          ]
          

          • x: number

            The x-coordinate.

          • y: number

            The y-coordinate.

        • type: "drag"

          Specifies the event type. For a drag action, this property is always set to drag.

          • "drag"

        • keys: optional array of string or null

          The keys being held while dragging the mouse.

      • Keypress object { keys, type }

        A collection of keypresses the model would like to perform.

        • keys: array of string

          The combination of keys the model is requesting to be pressed. This is an array of strings, each representing a key.

        • type: "keypress"

          Specifies the event type. For a keypress action, this property is always set to keypress.

          • "keypress"

      • Move object { type, x, y, keys }

        A mouse move action.

        • type: "move"

          Specifies the event type. For a move action, this property is always set to move.

          • "move"

        • x: number

          The x-coordinate to move to.

        • y: number

          The y-coordinate to move to.

        • keys: optional array of string or null

          The keys being held while moving the mouse.

      • Screenshot object { type }

        A screenshot action.

        • type: "screenshot"

          Specifies the event type. For a screenshot action, this property is always set to screenshot.

          • "screenshot"

      • Scroll object { scroll_x, scroll_y, type, 3 more }

        A scroll action.

        • scroll_x: number

          The horizontal scroll distance.

        • scroll_y: number

          The vertical scroll distance.

        • type: "scroll"

          Specifies the event type. For a scroll action, this property is always set to scroll.

          • "scroll"

        • x: number

          The x-coordinate where the scroll occurred.

        • y: number

          The y-coordinate where the scroll occurred.

        • keys: optional array of string or null

          The keys being held while scrolling.

      • Type object { text, type }

        An action to type in text.

        • text: string

          The text to type.

        • type: "type"

          Specifies the event type. For a type action, this property is always set to type.

          • "type"

      • Wait object { type }

        A wait action.

        • type: "wait"

          Specifies the event type. For a wait action, this property is always set to wait.

          • "wait"

    • actions: optional ComputerActionList

      Flattened batched actions for computer_use. Each action includes an type discriminator and action-specific fields.

      • Click object { button, type, x, 2 more }

        A click action.

      • DoubleClick object { keys, type, x, y }

        A double click action.

      • Drag object { path, type, keys }

        A drag action.

      • Keypress object { keys, type }

        A collection of keypresses the model would like to perform.

      • Move object { type, x, y, keys }

        A mouse move action.

      • Screenshot object { type }

        A screenshot action.

      • Scroll object { scroll_x, scroll_y, type, 3 more }

        A scroll action.

      • Type object { text, type }

        An action to type in text.

      • Wait object { type }

        A wait action.

  • ComputerCallOutput object { call_id, output, type, 3 more }

    The output of a computer tool call.

    • call_id: string

      The ID of the computer tool call that produced the output.

    • output: ResponseComputerToolCallOutputScreenshot

      A computer screenshot image used with the computer use tool.

      • type: "computer_screenshot"

        Specifies the event type. For a computer screenshot, this property is always set to computer_screenshot.

        • "computer_screenshot"

      • file_id: optional string

        The identifier of an uploaded file that contains the screenshot.

      • image_url: optional string

        The URL of the screenshot image.

    • type: "computer_call_output"

      The type of the computer tool call output. Always computer_call_output.

      • "computer_call_output"

    • id: optional string or null

      The ID of the computer tool call output.

    • acknowledged_safety_checks: optional array of object { id, code, message } or null

      The safety checks reported by the API that have been acknowledged by the developer.

      • id: string

        The ID of the pending safety check.

      • code: optional string or null

        The type of the pending safety check.

      • message: optional string or null

        Details about the pending safety check.

    • status: optional "in_progress" or "completed" or "incomplete" or null

      The status of the message input. One of in_progress, completed, or incomplete. Populated when input items are returned via API.

      • "in_progress"

      • "completed"

      • "incomplete"

  • WebSearchCall object { id, status, type, action }

    The results of a web search tool call. See the web search guide for more information.

    • id: string

      The unique ID of the web search tool call.

    • status: "in_progress" or "searching" or "completed" or 2 more

      The status of the web search tool call.

      • "in_progress"

      • "searching"

      • "completed"

      • "failed"

      • "incomplete"

    • type: "web_search_call"

      The type of the web search tool call. Always web_search_call.

      • "web_search_call"

    • action: optional object { type, queries, query, sources } or object { type, url } or object { pattern, type, url }

      An object describing the specific action taken in this web search call. Includes details on how the model used the web (search, open_page, find_in_page).

      • Search object { type, queries, query, sources }

        Action type "search" - Performs a web search query.

        • type: "search"

          The action type.

          • "search"

        • queries: optional array of string

          The search queries.

        • query: optional string

          The search query.

        • sources: optional array of object { type, url }

          The sources used in the search.

          • type: "url"

            The type of source. Always url.

            • "url"

          • url: string

            The URL of the source.

      • OpenPage object { type, url }

        Action type "open_page" - Opens a specific URL from search results.

        • type: "open_page"

          The action type.

          • "open_page"

        • url: optional string or null

          The URL opened by the model.

      • FindInPage object { pattern, type, url }

        Action type "find_in_page": Searches for a pattern within a loaded page.

        • pattern: string

          The pattern or text to search for within the page.

        • type: "find_in_page"

          The action type.

          • "find_in_page"

        • url: string

          The URL of the page searched for the pattern.

  • FunctionCall object { arguments, call_id, name, 6 more }

    A tool call to run a function. See the function calling guide for more information.

    • arguments: string

      A JSON string of the arguments to pass to the function.

    • call_id: string

      The unique ID of the function tool call generated by the model.

    • name: string

      The name of the function to run.

    • type: "function_call"

      The type of the function tool call. Always function_call.

      • "function_call"

    • id: optional string

      The unique ID of the function tool call.

    • async: optional boolean

      Whether the function tool call runs asynchronously.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          • "program"

    • namespace: optional string

      The namespace of the function to run.

    • status: optional "in_progress" or "completed" or "incomplete"

      The status of the item. One of in_progress, completed, or incomplete. Populated when items are returned via API.

      • "in_progress"

      • "completed"

      • "incomplete"

  • FunctionCallOutput object { output, type, id, 5 more }

    The output of a function tool call.

    • output: string or array of ResponseInputTextContent or ResponseInputImageContent or ResponseInputFileContent

      Text, image, or file output of the function tool call.

      • string

        A JSON string of the output of the function tool call.

      • array of ResponseInputTextContent or ResponseInputImageContent or ResponseInputFileContent

        An array of content outputs (text, image, file) for the function tool call.

        • ResponseInputTextContent object { text, type, prompt_cache_breakpoint }

          A text input to the model.

          • text: string

            The text input to the model.

          • type: "input_text"

            The type of the input item. Always input_text.

            • "input_text"

          • prompt_cache_breakpoint: optional object { mode } or null

            Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request's prompt_cache_options.ttl; the boundary is not rounded to a token block.

            • mode: "explicit"

              The breakpoint mode. Always explicit.

              • "explicit"

        • ResponseInputImageContent object { type, detail, file_id, 2 more }

          An image input to the model. Learn about image inputs

          • type: "input_image"

            The type of the input item. Always input_image.

            • "input_image"

          • detail: optional ImageDetail or null

            The detail level of the image to be sent to the model. One of high, low, auto, or original. Defaults to auto.

          • file_id: optional string or null

            The ID of the file to be sent to the model.

          • image_url: optional string or null

            The URL of the image to be sent to the model. A fully qualified URL or base64 encoded image in a data URL.

          • prompt_cache_breakpoint: optional object { mode } or null

            Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request's prompt_cache_options.ttl; the boundary is not rounded to a token block.

            • mode: "explicit"

              The breakpoint mode. Always explicit.

              • "explicit"

        • ResponseInputFileContent object { type, detail, file_data, 4 more }

          A file input to the model.

          • type: "input_file"

            The type of the input item. Always input_file.

            • "input_file"

          • detail: optional "auto" or "low" or "high"

            The detail level of the file to be sent to the model. Use auto to let the system select the detail level; for GPT-5.6 and later models, auto uses high-quality rendering, which may increase input token usage. Use low for lower-cost rendering, or high to render the file at higher quality. Defaults to auto.

            • "auto"

            • "low"

            • "high"

          • file_data: optional string or null

            The base64-encoded data of the file to be sent to the model.

          • file_id: optional string or null

            The ID of the file to be sent to the model.

          • file_url: optional string or null

            The URL of the file to be sent to the model.

          • filename: optional string or null

            The name of the file to be sent to the model.

          • prompt_cache_breakpoint: optional object { mode } or null

            Marks the exact end of a reusable prompt prefix. The breakpoint inherits its TTL from the request's prompt_cache_options.ttl; the boundary is not rounded to a token block.

            • mode: "explicit"

              The breakpoint mode. Always explicit.

              • "explicit"

    • type: "function_call_output"

      The type of the function tool call output. Always function_call_output.

      • "function_call_output"

    • id: optional string or null

      The unique ID of the function tool call output. Populated when this item is returned via API.

    • call_id: optional string or null

      The unique ID of the function tool call generated by the model.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          The caller type. Always direct.

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          The caller type. Always program.

          • "program"

    • name: optional string or null

      The name of the tool that produced the output.

    • namespace: optional string or null

      The namespace of the tool that produced the output.

    • status: optional "in_progress" or "completed" or "incomplete" or null

      The status of the item. One of in_progress, completed, or incomplete. Populated when items are returned via API.

      • "in_progress"

      • "completed"

      • "incomplete"

  • ToolSearchCall object { arguments, type, id, 3 more }

    • arguments: unknown

      The arguments supplied to the tool search call.

    • type: "tool_search_call"

      The item type. Always tool_search_call.

      • "tool_search_call"

    • id: optional string or null

      The unique ID of this tool search call.

    • call_id: optional string or null

      The unique ID of the tool search call generated by the model.

    • execution: optional "server" or "client"

      Whether tool search was executed by the server or by the client.

      • "server"

      • "client"

    • status: optional "in_progress" or "completed" or "incomplete" or null

      The status of the tool search call.

      • "in_progress"

      • "completed"

      • "incomplete"

  • ToolSearchOutput object { tools, type, id, 3 more }

    • tools: array of object { name, parameters, strict, 6 more } or object { type, vector_store_ids, filters, 2 more } or object { type } or 13 more

      The loaded tool definitions returned by the tool search output.

      • Function object { name, parameters, strict, 6 more }

        Defines a function in your own code the model can choose to call. Learn more about function calling.

        • name: string

          The name of the function to call.

        • parameters: map[unknown] or null

          A JSON schema object describing the parameters of the function.

        • strict: boolean or null

          Whether strict parameter validation is enforced for this function tool.

        • type: "function"

          The type of the function tool. Always function.

          • "function"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • async: optional boolean

        • defer_loading: optional boolean

          Whether this function is deferred and loaded via tool search.

        • description: optional string or null

          A description of the function. Used by the model to determine whether or not to call the function.

        • output_schema: optional map[unknown] or null

          A JSON schema object describing the JSON value encoded in string outputs for this function.

      • FileSearch object { type, vector_store_ids, filters, 2 more }

        A tool that searches for relevant content from uploaded files. Learn more about the file search tool.

        • type: "file_search"

          The type of the file search tool. Always file_search.

          • "file_search"

        • vector_store_ids: array of string

          The IDs of the vector stores to search.

        • filters: optional ComparisonFilter or CompoundFilter or null

          A filter to apply.

          • ComparisonFilter object { key, type, value }

            A filter used to compare a specified attribute key to a given value using a defined comparison operation.

            • key: string

              The key to compare against the value.

            • type: "eq" or "ne" or "gt" or 5 more

              Specifies the comparison operator: eq, ne, gt, gte, lt, lte, in, nin.

              • eq: equals

              • ne: not equal

              • gt: greater than

              • gte: greater than or equal

              • lt: less than

              • lte: less than or equal

              • in: in

              • nin: not in

              • "eq"

              • "ne"

              • "gt"

              • "gte"

              • "lt"

              • "lte"

              • "in"

              • "nin"

            • value: string or number or boolean or array of string or number

              The value to compare against the attribute key; supports string, number, or boolean types.

              • string

              • number

              • boolean

              • array of string or number

                • string

                • number

          • CompoundFilter object { filters, type }

            Combine multiple filters using and or or.

            • filters: array of ComparisonFilter or CompoundFilter

              Array of filters to combine. Items can be ComparisonFilter or CompoundFilter.

              • ComparisonFilter object { key, type, value }

                A filter used to compare a specified attribute key to a given value using a defined comparison operation.

              • CompoundFilter object { filters, type }

                Combine multiple filters using and or or.

            • type: "and" or "or"

              Type of operation: and or or.

              • "and"

              • "or"

        • max_num_results: optional number

          The maximum number of results to return. This number should be between 1 and 50 inclusive.

        • ranking_options: optional object { hybrid_search, ranker, score_threshold }

          Ranking options for search.

          • hybrid_search: optional object { embedding_weight, text_weight }

            Weights that control how reciprocal rank fusion balances semantic embedding matches versus sparse keyword matches when hybrid search is enabled.

            • embedding_weight: number

              The weight of the embedding in the reciprocal ranking fusion.

            • text_weight: number

              The weight of the text in the reciprocal ranking fusion.

          • ranker: optional "auto" or "default-2024-11-15"

            The ranker to use for the file search.

            • "auto"

            • "default-2024-11-15"

          • score_threshold: optional number

            The score threshold for the file search, a number between 0 and 1. Numbers closer to 1 will attempt to return only the most relevant results, but may return fewer results.

      • Computer object { type }

        A tool that controls a virtual computer. Learn more about the computer tool.

        • type: "computer"

          The type of the computer tool. Always computer.

          • "computer"

      • ComputerUsePreview object { display_height, display_width, environment, type }

        A tool that controls a virtual computer. Learn more about the computer tool.

        • display_height: number

          The height of the computer display.

        • display_width: number

          The width of the computer display.

        • environment: "windows" or "mac" or "linux" or 2 more

          The type of computer environment to control.

          • "windows"

          • "mac"

          • "linux"

          • "ubuntu"

          • "browser"

        • type: "computer_use_preview"

          The type of the computer use tool. Always computer_use_preview.

          • "computer_use_preview"

      • WebSearch object { type, external_web_access, filters, 2 more }

        Search the Internet for sources related to the prompt. Learn more about the web search tool.

        • type: "web_search" or "web_search_2025_08_26"

          The type of the web search tool. One of web_search or web_search_2025_08_26.

          • "web_search"

          • "web_search_2025_08_26"

        • external_web_access: optional boolean

          Allow live internet access for web search. Defaults to true when omitted. When false, the web search tool runs in offline/cache-only mode and will not fetch new external content.

        • filters: optional object { allowed_domains } or null

          Filters for the search.

          • allowed_domains: optional array of string or null

            Allowed domains for the search. If not provided, all domains are allowed. Subdomains of the provided domains are allowed as well.

            Example: ["pubmed.ncbi.nlm.nih.gov"]

        • search_context_size: optional "low" or "medium" or "high"

          High level guidance for the amount of context window space to use for the search. One of low, medium, or high. medium is the default.

          • "low"

          • "medium"

          • "high"

        • user_location: optional object { city, country, region, 2 more } or null

          The approximate location of the user. If omitted or null, defaults to the United States. To avoid this fallback, pass {"type": "approximate"} without location fields. To localize results, provide the relevant location fields.

          • city: optional string or null

            Free text input for the city of the user, e.g. San Francisco.

          • country: optional string or null

            The two-letter ISO country code of the user, e.g. US.

          • region: optional string or null

            Free text input for the region of the user, e.g. California.

          • timezone: optional string or null

            The IANA timezone of the user, e.g. America/Los_Angeles.

          • type: optional "approximate"

            The type of location approximation. Always approximate.

            • "approximate"

      • Mcp object { server_label, type, allowed_callers, 9 more }

        Give the model access to additional tools via remote Model Context Protocol (MCP) servers. Learn more about MCP.

        • server_label: string

          A label for this MCP server, used to identify it in tool calls.

        • type: "mcp"

          The type of the MCP tool. Always mcp.

          • "mcp"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • allowed_tools: optional array of string or object { read_only, tool_names } or null

          List of allowed tool names or a filter object.

          • McpAllowedTools = array of string

            A string array of allowed tool names

          • McpToolFilter object { read_only, tool_names }

            A filter object to specify which tools are allowed.

            • read_only: optional boolean

              Indicates whether or not a tool modifies data or is read-only. If an MCP server is annotated with readOnlyHint, it will match this filter.

            • tool_names: optional array of string

              List of allowed tool names.

        • authorization: optional string

          An OAuth access token that can be used with a remote MCP server, either with a custom MCP server URL or a service connector. Your application must handle the OAuth authorization flow and provide the token here.

        • connector_id: optional "connector_dropbox" or "connector_gmail" or "connector_googlecalendar" or 5 more

          Identifier for service connectors, like those available in ChatGPT. One of server_url, connector_id, or tunnel_id must be provided. Learn more about service connectors here.

          This field is deprecated for models released after September 1, 2026. Use server_url to connect to a remote MCP server, or tunnel_id to connect through a Secure MCP Tunnel.

          Currently supported connector_id values are:

          • Dropbox: connector_dropbox

          • Gmail: connector_gmail

          • Google Calendar: connector_googlecalendar

          • Google Drive: connector_googledrive

          • Microsoft Teams: connector_microsoftteams

          • Outlook Calendar: connector_outlookcalendar

          • Outlook Email: connector_outlookemail

          • SharePoint: connector_sharepoint

          • "connector_dropbox"

          • "connector_gmail"

          • "connector_googlecalendar"

          • "connector_googledrive"

          • "connector_microsoftteams"

          • "connector_outlookcalendar"

          • "connector_outlookemail"

          • "connector_sharepoint"

        • defer_loading: optional boolean

          Whether this MCP tool is deferred and discovered via tool search.

        • headers: optional map[string] or null

          Optional HTTP headers to send to the MCP server. Use for authentication or other purposes.

        • require_approval: optional object { always, never } or "always" or "never" or null

          Specify which of the MCP server's tools require approval.

          • McpToolApprovalFilter object { always, never }

            Specify which of the MCP server's tools require approval. Can be always, never, or a filter object associated with tools that require approval.

            • always: optional object { read_only, tool_names }

              A filter object to specify which tools are allowed.

              • read_only: optional boolean

                Indicates whether or not a tool modifies data or is read-only. If an MCP server is annotated with readOnlyHint, it will match this filter.

              • tool_names: optional array of string

                List of allowed tool names.

            • never: optional object { read_only, tool_names }

              A filter object to specify which tools are allowed.

              • read_only: optional boolean

                Indicates whether or not a tool modifies data or is read-only. If an MCP server is annotated with readOnlyHint, it will match this filter.

              • tool_names: optional array of string

                List of allowed tool names.

          • McpToolApprovalSetting = "always" or "never"

            Specify a single approval policy for all tools. One of always or never. When set to always, all tools will require approval. When set to never, all tools will not require approval.

            • "always"

            • "never"

        • server_description: optional string

          Optional description of the MCP server, used to provide more context.

        • server_url: optional string

          The URL for the MCP server. One of server_url, connector_id, or tunnel_id must be provided.

        • tunnel_id: optional string

          The Secure MCP Tunnel ID to use instead of a direct server URL. One of server_url, connector_id, or tunnel_id must be provided.

      • CodeInterpreter object { container, type, allowed_callers }

        A tool that runs Python code to help generate a response to a prompt.

        • container: string or object { type, file_ids, memory_limit, network_policy }

          The code interpreter container. Can be a container ID or an object that specifies uploaded file IDs to make available to your code, along with an optional memory_limit setting.

          • string

            The container ID.

          • CodeInterpreterToolAuto object { type, file_ids, memory_limit, network_policy }

            Configuration for a code interpreter container. Optionally specify the IDs of the files to run the code on.

            • type: "auto"

              Always auto.

              • "auto"

            • file_ids: optional array of string

              An optional list of uploaded files to make available to your code.

            • memory_limit: optional "1g" or "4g" or "16g" or "64g" or null

              The memory limit for the code interpreter container.

              • "1g"

              • "4g"

              • "16g"

              • "64g"

            • network_policy: optional ContainerNetworkPolicyDisabled or ContainerNetworkPolicyAllowlist

              Network access policy for the container.

              • ContainerNetworkPolicyDisabled object { type }

                • type: "disabled"

                  Disable outbound network access. Always disabled.

                  • "disabled"

              • ContainerNetworkPolicyAllowlist object { allowed_domains, type, domain_secrets }

                • allowed_domains: array of string

                  A list of allowed domains when type is allowlist.

                • type: "allowlist"

                  Allow outbound network access only to specified domains. Always allowlist.

                  • "allowlist"

                • domain_secrets: optional array of ContainerNetworkPolicyDomainSecret

                  Optional domain-scoped secrets for allowlisted domains.

                  • domain: string

                    The domain associated with the secret.

                  • name: string

                    The name of the secret to inject for the domain.

                  • value: string

                    The secret value to inject for the domain.

        • type: "code_interpreter"

          The type of the code interpreter tool. Always code_interpreter.

          • "code_interpreter"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

      • ProgrammaticToolCalling object { type }

        • type: "programmatic_tool_calling"

          The type of the tool. Always programmatic_tool_calling.

          • "programmatic_tool_calling"

      • ImageGeneration object { type, action, background, 9 more }

        A tool that generates images using the GPT image models.

        • type: "image_generation"

          The type of the image generation tool. Always image_generation.

          • "image_generation"

        • action: optional "generate" or "edit" or "auto"

          Whether to generate a new image or edit an existing image. Default: auto.

          • "generate"

          • "edit"

          • "auto"

        • background: optional "transparent" or "opaque" or "auto"

          Set the background of the generated image. One of transparent, opaque, or auto. gpt-image-2.5-sunburst and gpt-image-2.5-flare, including their 2026-09-08 snapshots, support opaque and transparent backgrounds. Transparent backgrounds are available for supported GPT Image models. For gpt-image-2 and gpt-image-2-2026-04-21, this support is in preview. When using transparent, set the output format to png or webp. Default: auto.

          • "transparent"

          • "opaque"

          • "auto"

        • input_fidelity: optional "high" or "low" or null

          Control how much effort the model will exert to match the style and features, especially facial features, of input images. This parameter is only supported for gpt-image-1 and gpt-image-1.5 and later models, unsupported for gpt-image-1-mini. Supports high and low. Defaults to low.

          • "high"

          • "low"

        • input_image_mask: optional object { file_id, image_url }

          Optional mask for inpainting. Contains image_url (string, optional) and file_id (string, optional).

          • file_id: optional string

            File ID for the mask image.

          • image_url: optional string

            Base64-encoded mask image.

        • model: optional string or "gpt-image-1" or "gpt-image-1-mini" or "gpt-image-1.5" or 6 more

          The image generation model to use. One of gpt-image-1, gpt-image-1-mini, gpt-image-1.5, gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, gpt-image-2.5-flare-2026-09-08, or chatgpt-image-latest. Default: gpt-image-1.

          • string

          • "gpt-image-1" or "gpt-image-1-mini" or "gpt-image-1.5" or 6 more

            The image generation model to use. One of gpt-image-1, gpt-image-1-mini, gpt-image-1.5, gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, gpt-image-2.5-flare-2026-09-08, or chatgpt-image-latest. Default: gpt-image-1.

            • "gpt-image-1"

            • "gpt-image-1-mini"

            • "gpt-image-1.5"

            • "gpt-image-2"

            • "gpt-image-2-2026-04-21"

            • "gpt-image-2.5-sunburst"

            • "gpt-image-2.5-sunburst-2026-09-08"

            • "gpt-image-2.5-flare"

            • "gpt-image-2.5-flare-2026-09-08"

        • moderation: optional "auto" or "low"

          Moderation level for the generated image. Default: auto.

          • "auto"

          • "low"

        • output_compression: optional number

          Compression level for the output image. Default: 100.

        • output_format: optional "png" or "webp" or "jpeg"

          The output format of the generated image. One of png, webp, or jpeg. Default: png.

          • "png"

          • "webp"

          • "jpeg"

        • partial_images: optional number

          Number of partial images to generate in streaming mode, from 0 (default value) to 3.

        • quality: optional "low" or "medium" or "high" or 3 more

          The quality of the generated image. The GPT image models support low, medium, and high. gpt-image-2.5-sunburst and gpt-image-2.5-flare, including their 2026-09-08 snapshots, also support xhigh and max. Default: auto.

          • "low"

          • "medium"

          • "high"

          • "xhigh"

          • "max"

          • "auto"

        • size: optional string or "1024x1024" or "1024x1536" or "1536x1024" or "auto"

          The size of the generated images. For gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, and gpt-image-2.5-flare-2026-09-08, arbitrary resolutions are supported as WIDTHxHEIGHT strings, for example 1536x864. Width and height must both be divisible by 16 and the requested aspect ratio must be between 1:3 and 3:1. Resolutions above 2560x1440 are experimental, and the maximum supported resolution is 3840x2160. The requested size must also satisfy the model's current pixel and edge limits. The standard sizes 1024x1024, 1536x1024, and 1024x1536 are supported by the GPT image models; auto is supported for models that allow automatic sizing.

          • string

          • "1024x1024" or "1024x1536" or "1536x1024" or "auto"

            The size of the generated images. For gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, and gpt-image-2.5-flare-2026-09-08, arbitrary resolutions are supported as WIDTHxHEIGHT strings, for example 1536x864. Width and height must both be divisible by 16 and the requested aspect ratio must be between 1:3 and 3:1. Resolutions above 2560x1440 are experimental, and the maximum supported resolution is 3840x2160. The requested size must also satisfy the model's current pixel and edge limits. The standard sizes 1024x1024, 1536x1024, and 1024x1536 are supported by the GPT image models; auto is supported for models that allow automatic sizing.

            • "1024x1024"

            • "1024x1536"

            • "1536x1024"

            • "auto"

      • LocalShell object { type }

        A tool that allows the model to execute shell commands in a local environment.

        • type: "local_shell"

          The type of the local shell tool. Always local_shell.

          • "local_shell"

      • Shell object { type, allowed_callers, environment }

        A tool that allows the model to execute shell commands.

        • type: "shell"

          The type of the shell tool. Always shell.

          • "shell"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • environment: optional ContainerAuto or LocalEnvironment or ContainerReference or null

          • ContainerAuto object { type, file_ids, memory_limit, 2 more }

            • type: "container_auto"

              Automatically creates a container for this request

              • "container_auto"

            • file_ids: optional array of string

              An optional list of uploaded files to make available to your code.

            • memory_limit: optional "1g" or "4g" or "16g" or "64g" or null

              The memory limit for the container.

              • "1g"

              • "4g"

              • "16g"

              • "64g"

            • network_policy: optional ContainerNetworkPolicyDisabled or ContainerNetworkPolicyAllowlist

              Network access policy for the container.

              • ContainerNetworkPolicyDisabled object { type }

              • ContainerNetworkPolicyAllowlist object { allowed_domains, type, domain_secrets }

            • skills: optional array of SkillReference or InlineSkill

              An optional list of skills referenced by id or inline data.

              • SkillReference object { skill_id, type, version }

                • skill_id: string

                  The ID of the referenced skill.

                • type: "skill_reference"

                  References a skill created with the /v1/skills endpoint.

                  • "skill_reference"

                • version: optional string

                  Optional skill version. Use a positive integer or 'latest'. Omit for default.

              • InlineSkill object { description, name, source, type }

                • description: string

                  The description of the skill.

                • name: string

                  The name of the skill.

                • source: InlineSkillSource

                  Inline skill payload

                  • data: string

                    Base64-encoded skill zip bundle.

                  • media_type: "application/zip"

                    The media type of the inline skill payload. Must be application/zip.

                    • "application/zip"

                  • type: "base64"

                    The type of the inline skill source. Must be base64.

                    • "base64"

                • type: "inline"

                  Defines an inline skill for this request.

                  • "inline"

          • LocalEnvironment object { type, skills }

            • type: "local"

              Use a local computer environment.

              • "local"

            • skills: optional array of LocalSkill

              An optional list of skills.

              • description: string

                The description of the skill.

              • name: string

                The name of the skill.

              • path: string

                The path to the directory containing the skill.

          • ContainerReference object { container_id, type }

            • container_id: string

              The ID of the referenced container.

            • type: "container_reference"

              References a container created with the /v1/containers endpoint

              • "container_reference"

      • Custom object { name, type, allowed_callers, 4 more }

        A custom tool that processes input using a specified format. Learn more about custom tools

        • name: string

          The name of the custom tool, used to identify it in tool calls.

        • type: "custom"

          The type of the custom tool. Always custom.

          • "custom"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • async: optional boolean

          Whether the tool response can be returned asynchronously versus immediately returned on next response creation.

        • defer_loading: optional boolean

          Whether this tool should be deferred and discovered via tool search.

        • description: optional string

          Optional description of the custom tool, used to provide more context.

        • format: optional CustomToolInputFormat

          The input format for the custom tool. Default is unconstrained text.

          • Text object { type }

            Unconstrained free-form text.

            • type: "text"

              Unconstrained text format. Always text.

              • "text"

          • Grammar object { definition, syntax, type }

            A grammar defined by the user.

            • definition: string

              The grammar definition.

            • syntax: "lark" or "regex"

              The syntax of the grammar definition. One of lark or regex.

              • "lark"

              • "regex"

            • type: "grammar"

              Grammar format. Always grammar.

              • "grammar"

      • Namespace object { description, name, tools, type }

        Groups function/custom tools under a shared namespace.

        • description: string

          A description of the namespace shown to the model.

        • name: string

          The namespace name used in tool calls (for example, crm).

        • tools: array of object { name, type, allowed_callers, 6 more } or object { name, type, allowed_callers, 4 more }

          The function/custom tools available inside this namespace.

          • Function object { name, type, allowed_callers, 6 more }

            • name: string

            • type: "function"

              • "function"

            • allowed_callers: optional array of "direct" or "programmatic" or null

              The tool invocation context(s).

              • "direct"

              • "programmatic"

            • async: optional boolean

              Whether the tool response can be returned asynchronously versus immediately returned on next response creation.

            • defer_loading: optional boolean

              Whether this function should be deferred and discovered via tool search.

            • description: optional string or null

            • output_schema: optional map[unknown] or null

              A JSON Schema describing the JSON value encoded in string outputs for this function tool. This does not describe content-array outputs.

            • parameters: optional unknown or null

            • strict: optional boolean or null

              Whether to enforce strict parameter validation. If omitted, Responses attempts to use strict validation when the schema is compatible, and falls back to non-strict validation otherwise.

          • Custom object { name, type, allowed_callers, 4 more }

            A custom tool that processes input using a specified format. Learn more about custom tools

            • name: string

              The name of the custom tool, used to identify it in tool calls.

            • type: "custom"

              The type of the custom tool. Always custom.

              • "custom"

            • allowed_callers: optional array of "direct" or "programmatic" or null

              The tool invocation context(s).

              • "direct"

              • "programmatic"

            • async: optional boolean

              Whether the tool response can be returned asynchronously versus immediately returned on next response creation.

            • defer_loading: optional boolean

              Whether this tool should be deferred and discovered via tool search.

            • description: optional string

              Optional description of the custom tool, used to provide more context.

            • format: optional CustomToolInputFormat

              The input format for the custom tool. Default is unconstrained text.

        • type: "namespace"

          The type of the tool. Always namespace.

          • "namespace"

      • ToolSearch object { type, description, execution, parameters }

        Hosted or BYOT tool search configuration for deferred tools.

        • type: "tool_search"

          The type of the tool. Always tool_search.

          • "tool_search"

        • description: optional string or null

          Description shown to the model for a client-executed tool search tool.

        • execution: optional "server" or "client"

          Whether tool search is executed by the server or by the client.

          • "server"

          • "client"

        • parameters: optional unknown or null

          Parameter schema for a client-executed tool search tool.

      • WebSearchPreview object { type, search_content_types, search_context_size, user_location }

        This tool searches the web for relevant results to use in a response. Learn more about the web search tool.

        • type: "web_search_preview" or "web_search_preview_2025_03_11"

          The type of the web search tool. One of web_search_preview or web_search_preview_2025_03_11.

          • "web_search_preview"

          • "web_search_preview_2025_03_11"

        • search_content_types: optional array of "text" or "image"

          • "text"

          • "image"

        • search_context_size: optional "low" or "medium" or "high"

          High level guidance for the amount of context window space to use for the search. One of low, medium, or high. medium is the default.

          • "low"

          • "medium"

          • "high"

        • user_location: optional object { type, city, country, 2 more } or null

          The approximate location of the user. If omitted or null, defaults to the United States. To avoid this fallback, pass {"type": "approximate"} without location fields. To localize results, provide the relevant location fields.

          • type: "approximate"

            The type of location approximation. Always approximate.

            • "approximate"

          • city: optional string or null

            Free text input for the city of the user, e.g. San Francisco.

          • country: optional string or null

            The two-letter ISO country code of the user, e.g. US.

          • region: optional string or null

            Free text input for the region of the user, e.g. California.

          • timezone: optional string or null

            The IANA timezone of the user, e.g. America/Los_Angeles.

      • ApplyPatch object { type, allowed_callers }

        Allows the assistant to create, delete, or update files using unified diffs.

        • type: "apply_patch"

          The type of the tool. Always apply_patch.

          • "apply_patch"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

    • type: "tool_search_output"

      The item type. Always tool_search_output.

      • "tool_search_output"

    • id: optional string or null

      The unique ID of this tool search output.

    • call_id: optional string or null

      The unique ID of the tool search call generated by the model.

    • execution: optional "server" or "client"

      Whether tool search was executed by the server or by the client.

      • "server"

      • "client"

    • status: optional "in_progress" or "completed" or "incomplete" or null

      The status of the tool search output.

      • "in_progress"

      • "completed"

      • "incomplete"

  • AdditionalTools object { role, tools, type, id }

    • role: "developer"

      The role that provided the additional tools. Only developer is supported.

      • "developer"

    • tools: array of object { name, parameters, strict, 6 more } or object { type, vector_store_ids, filters, 2 more } or object { type } or 13 more

      A list of additional tools made available at this item.

      • Function object { name, parameters, strict, 6 more }

        Defines a function in your own code the model can choose to call. Learn more about function calling.

        • name: string

          The name of the function to call.

        • parameters: map[unknown] or null

          A JSON schema object describing the parameters of the function.

        • strict: boolean or null

          Whether strict parameter validation is enforced for this function tool.

        • type: "function"

          The type of the function tool. Always function.

          • "function"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • async: optional boolean

        • defer_loading: optional boolean

          Whether this function is deferred and loaded via tool search.

        • description: optional string or null

          A description of the function. Used by the model to determine whether or not to call the function.

        • output_schema: optional map[unknown] or null

          A JSON schema object describing the JSON value encoded in string outputs for this function.

      • FileSearch object { type, vector_store_ids, filters, 2 more }

        A tool that searches for relevant content from uploaded files. Learn more about the file search tool.

        • type: "file_search"

          The type of the file search tool. Always file_search.

          • "file_search"

        • vector_store_ids: array of string

          The IDs of the vector stores to search.

        • filters: optional ComparisonFilter or CompoundFilter or null

          A filter to apply.

          • ComparisonFilter object { key, type, value }

            A filter used to compare a specified attribute key to a given value using a defined comparison operation.

          • CompoundFilter object { filters, type }

            Combine multiple filters using and or or.

        • max_num_results: optional number

          The maximum number of results to return. This number should be between 1 and 50 inclusive.

        • ranking_options: optional object { hybrid_search, ranker, score_threshold }

          Ranking options for search.

          • hybrid_search: optional object { embedding_weight, text_weight }

            Weights that control how reciprocal rank fusion balances semantic embedding matches versus sparse keyword matches when hybrid search is enabled.

            • embedding_weight: number

              The weight of the embedding in the reciprocal ranking fusion.

            • text_weight: number

              The weight of the text in the reciprocal ranking fusion.

          • ranker: optional "auto" or "default-2024-11-15"

            The ranker to use for the file search.

            • "auto"

            • "default-2024-11-15"

          • score_threshold: optional number

            The score threshold for the file search, a number between 0 and 1. Numbers closer to 1 will attempt to return only the most relevant results, but may return fewer results.

      • Computer object { type }

        A tool that controls a virtual computer. Learn more about the computer tool.

        • type: "computer"

          The type of the computer tool. Always computer.

          • "computer"

      • ComputerUsePreview object { display_height, display_width, environment, type }

        A tool that controls a virtual computer. Learn more about the computer tool.

        • display_height: number

          The height of the computer display.

        • display_width: number

          The width of the computer display.

        • environment: "windows" or "mac" or "linux" or 2 more

          The type of computer environment to control.

          • "windows"

          • "mac"

          • "linux"

          • "ubuntu"

          • "browser"

        • type: "computer_use_preview"

          The type of the computer use tool. Always computer_use_preview.

          • "computer_use_preview"

      • WebSearch object { type, external_web_access, filters, 2 more }

        Search the Internet for sources related to the prompt. Learn more about the web search tool.

        • type: "web_search" or "web_search_2025_08_26"

          The type of the web search tool. One of web_search or web_search_2025_08_26.

          • "web_search"

          • "web_search_2025_08_26"

        • external_web_access: optional boolean

          Allow live internet access for web search. Defaults to true when omitted. When false, the web search tool runs in offline/cache-only mode and will not fetch new external content.

        • filters: optional object { allowed_domains } or null

          Filters for the search.

          • allowed_domains: optional array of string or null

            Allowed domains for the search. If not provided, all domains are allowed. Subdomains of the provided domains are allowed as well.

            Example: ["pubmed.ncbi.nlm.nih.gov"]

        • search_context_size: optional "low" or "medium" or "high"

          High level guidance for the amount of context window space to use for the search. One of low, medium, or high. medium is the default.

          • "low"

          • "medium"

          • "high"

        • user_location: optional object { city, country, region, 2 more } or null

          The approximate location of the user. If omitted or null, defaults to the United States. To avoid this fallback, pass {"type": "approximate"} without location fields. To localize results, provide the relevant location fields.

          • city: optional string or null

            Free text input for the city of the user, e.g. San Francisco.

          • country: optional string or null

            The two-letter ISO country code of the user, e.g. US.

          • region: optional string or null

            Free text input for the region of the user, e.g. California.

          • timezone: optional string or null

            The IANA timezone of the user, e.g. America/Los_Angeles.

          • type: optional "approximate"

            The type of location approximation. Always approximate.

            • "approximate"

      • Mcp object { server_label, type, allowed_callers, 9 more }

        Give the model access to additional tools via remote Model Context Protocol (MCP) servers. Learn more about MCP.

        • server_label: string

          A label for this MCP server, used to identify it in tool calls.

        • type: "mcp"

          The type of the MCP tool. Always mcp.

          • "mcp"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • allowed_tools: optional array of string or object { read_only, tool_names } or null

          List of allowed tool names or a filter object.

          • McpAllowedTools = array of string

            A string array of allowed tool names

          • McpToolFilter object { read_only, tool_names }

            A filter object to specify which tools are allowed.

            • read_only: optional boolean

              Indicates whether or not a tool modifies data or is read-only. If an MCP server is annotated with readOnlyHint, it will match this filter.

            • tool_names: optional array of string

              List of allowed tool names.

        • authorization: optional string

          An OAuth access token that can be used with a remote MCP server, either with a custom MCP server URL or a service connector. Your application must handle the OAuth authorization flow and provide the token here.

        • connector_id: optional "connector_dropbox" or "connector_gmail" or "connector_googlecalendar" or 5 more

          Identifier for service connectors, like those available in ChatGPT. One of server_url, connector_id, or tunnel_id must be provided. Learn more about service connectors here.

          This field is deprecated for models released after September 1, 2026. Use server_url to connect to a remote MCP server, or tunnel_id to connect through a Secure MCP Tunnel.

          Currently supported connector_id values are:

          • Dropbox: connector_dropbox

          • Gmail: connector_gmail

          • Google Calendar: connector_googlecalendar

          • Google Drive: connector_googledrive

          • Microsoft Teams: connector_microsoftteams

          • Outlook Calendar: connector_outlookcalendar

          • Outlook Email: connector_outlookemail

          • SharePoint: connector_sharepoint

          • "connector_dropbox"

          • "connector_gmail"

          • "connector_googlecalendar"

          • "connector_googledrive"

          • "connector_microsoftteams"

          • "connector_outlookcalendar"

          • "connector_outlookemail"

          • "connector_sharepoint"

        • defer_loading: optional boolean

          Whether this MCP tool is deferred and discovered via tool search.

        • headers: optional map[string] or null

          Optional HTTP headers to send to the MCP server. Use for authentication or other purposes.

        • require_approval: optional object { always, never } or "always" or "never" or null

          Specify which of the MCP server's tools require approval.

          • McpToolApprovalFilter object { always, never }

            Specify which of the MCP server's tools require approval. Can be always, never, or a filter object associated with tools that require approval.

            • always: optional object { read_only, tool_names }

              A filter object to specify which tools are allowed.

              • read_only: optional boolean

                Indicates whether or not a tool modifies data or is read-only. If an MCP server is annotated with readOnlyHint, it will match this filter.

              • tool_names: optional array of string

                List of allowed tool names.

            • never: optional object { read_only, tool_names }

              A filter object to specify which tools are allowed.

              • read_only: optional boolean

                Indicates whether or not a tool modifies data or is read-only. If an MCP server is annotated with readOnlyHint, it will match this filter.

              • tool_names: optional array of string

                List of allowed tool names.

          • McpToolApprovalSetting = "always" or "never"

            Specify a single approval policy for all tools. One of always or never. When set to always, all tools will require approval. When set to never, all tools will not require approval.

            • "always"

            • "never"

        • server_description: optional string

          Optional description of the MCP server, used to provide more context.

        • server_url: optional string

          The URL for the MCP server. One of server_url, connector_id, or tunnel_id must be provided.

        • tunnel_id: optional string

          The Secure MCP Tunnel ID to use instead of a direct server URL. One of server_url, connector_id, or tunnel_id must be provided.

      • CodeInterpreter object { container, type, allowed_callers }

        A tool that runs Python code to help generate a response to a prompt.

        • container: string or object { type, file_ids, memory_limit, network_policy }

          The code interpreter container. Can be a container ID or an object that specifies uploaded file IDs to make available to your code, along with an optional memory_limit setting.

          • string

            The container ID.

          • CodeInterpreterToolAuto object { type, file_ids, memory_limit, network_policy }

            Configuration for a code interpreter container. Optionally specify the IDs of the files to run the code on.

            • type: "auto"

              Always auto.

              • "auto"

            • file_ids: optional array of string

              An optional list of uploaded files to make available to your code.

            • memory_limit: optional "1g" or "4g" or "16g" or "64g" or null

              The memory limit for the code interpreter container.

              • "1g"

              • "4g"

              • "16g"

              • "64g"

            • network_policy: optional ContainerNetworkPolicyDisabled or ContainerNetworkPolicyAllowlist

              Network access policy for the container.

              • ContainerNetworkPolicyDisabled object { type }

              • ContainerNetworkPolicyAllowlist object { allowed_domains, type, domain_secrets }

        • type: "code_interpreter"

          The type of the code interpreter tool. Always code_interpreter.

          • "code_interpreter"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

      • ProgrammaticToolCalling object { type }

        • type: "programmatic_tool_calling"

          The type of the tool. Always programmatic_tool_calling.

          • "programmatic_tool_calling"

      • ImageGeneration object { type, action, background, 9 more }

        A tool that generates images using the GPT image models.

        • type: "image_generation"

          The type of the image generation tool. Always image_generation.

          • "image_generation"

        • action: optional "generate" or "edit" or "auto"

          Whether to generate a new image or edit an existing image. Default: auto.

          • "generate"

          • "edit"

          • "auto"

        • background: optional "transparent" or "opaque" or "auto"

          Set the background of the generated image. One of transparent, opaque, or auto. gpt-image-2.5-sunburst and gpt-image-2.5-flare, including their 2026-09-08 snapshots, support opaque and transparent backgrounds. Transparent backgrounds are available for supported GPT Image models. For gpt-image-2 and gpt-image-2-2026-04-21, this support is in preview. When using transparent, set the output format to png or webp. Default: auto.

          • "transparent"

          • "opaque"

          • "auto"

        • input_fidelity: optional "high" or "low" or null

          Control how much effort the model will exert to match the style and features, especially facial features, of input images. This parameter is only supported for gpt-image-1 and gpt-image-1.5 and later models, unsupported for gpt-image-1-mini. Supports high and low. Defaults to low.

          • "high"

          • "low"

        • input_image_mask: optional object { file_id, image_url }

          Optional mask for inpainting. Contains image_url (string, optional) and file_id (string, optional).

          • file_id: optional string

            File ID for the mask image.

          • image_url: optional string

            Base64-encoded mask image.

        • model: optional string or "gpt-image-1" or "gpt-image-1-mini" or "gpt-image-1.5" or 6 more

          The image generation model to use. One of gpt-image-1, gpt-image-1-mini, gpt-image-1.5, gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, gpt-image-2.5-flare-2026-09-08, or chatgpt-image-latest. Default: gpt-image-1.

          • string

          • "gpt-image-1" or "gpt-image-1-mini" or "gpt-image-1.5" or 6 more

            The image generation model to use. One of gpt-image-1, gpt-image-1-mini, gpt-image-1.5, gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, gpt-image-2.5-flare-2026-09-08, or chatgpt-image-latest. Default: gpt-image-1.

            • "gpt-image-1"

            • "gpt-image-1-mini"

            • "gpt-image-1.5"

            • "gpt-image-2"

            • "gpt-image-2-2026-04-21"

            • "gpt-image-2.5-sunburst"

            • "gpt-image-2.5-sunburst-2026-09-08"

            • "gpt-image-2.5-flare"

            • "gpt-image-2.5-flare-2026-09-08"

        • moderation: optional "auto" or "low"

          Moderation level for the generated image. Default: auto.

          • "auto"

          • "low"

        • output_compression: optional number

          Compression level for the output image. Default: 100.

        • output_format: optional "png" or "webp" or "jpeg"

          The output format of the generated image. One of png, webp, or jpeg. Default: png.

          • "png"

          • "webp"

          • "jpeg"

        • partial_images: optional number

          Number of partial images to generate in streaming mode, from 0 (default value) to 3.

        • quality: optional "low" or "medium" or "high" or 3 more

          The quality of the generated image. The GPT image models support low, medium, and high. gpt-image-2.5-sunburst and gpt-image-2.5-flare, including their 2026-09-08 snapshots, also support xhigh and max. Default: auto.

          • "low"

          • "medium"

          • "high"

          • "xhigh"

          • "max"

          • "auto"

        • size: optional string or "1024x1024" or "1024x1536" or "1536x1024" or "auto"

          The size of the generated images. For gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, and gpt-image-2.5-flare-2026-09-08, arbitrary resolutions are supported as WIDTHxHEIGHT strings, for example 1536x864. Width and height must both be divisible by 16 and the requested aspect ratio must be between 1:3 and 3:1. Resolutions above 2560x1440 are experimental, and the maximum supported resolution is 3840x2160. The requested size must also satisfy the model's current pixel and edge limits. The standard sizes 1024x1024, 1536x1024, and 1024x1536 are supported by the GPT image models; auto is supported for models that allow automatic sizing.

          • string

          • "1024x1024" or "1024x1536" or "1536x1024" or "auto"

            The size of the generated images. For gpt-image-2, gpt-image-2-2026-04-21, gpt-image-2.5-sunburst, gpt-image-2.5-sunburst-2026-09-08, gpt-image-2.5-flare, and gpt-image-2.5-flare-2026-09-08, arbitrary resolutions are supported as WIDTHxHEIGHT strings, for example 1536x864. Width and height must both be divisible by 16 and the requested aspect ratio must be between 1:3 and 3:1. Resolutions above 2560x1440 are experimental, and the maximum supported resolution is 3840x2160. The requested size must also satisfy the model's current pixel and edge limits. The standard sizes 1024x1024, 1536x1024, and 1024x1536 are supported by the GPT image models; auto is supported for models that allow automatic sizing.

            • "1024x1024"

            • "1024x1536"

            • "1536x1024"

            • "auto"

      • LocalShell object { type }

        A tool that allows the model to execute shell commands in a local environment.

        • type: "local_shell"

          The type of the local shell tool. Always local_shell.

          • "local_shell"

      • Shell object { type, allowed_callers, environment }

        A tool that allows the model to execute shell commands.

        • type: "shell"

          The type of the shell tool. Always shell.

          • "shell"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • environment: optional ContainerAuto or LocalEnvironment or ContainerReference or null

          • ContainerAuto object { type, file_ids, memory_limit, 2 more }

          • LocalEnvironment object { type, skills }

          • ContainerReference object { container_id, type }

      • Custom object { name, type, allowed_callers, 4 more }

        A custom tool that processes input using a specified format. Learn more about custom tools

        • name: string

          The name of the custom tool, used to identify it in tool calls.

        • type: "custom"

          The type of the custom tool. Always custom.

          • "custom"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

        • async: optional boolean

          Whether the tool response can be returned asynchronously versus immediately returned on next response creation.

        • defer_loading: optional boolean

          Whether this tool should be deferred and discovered via tool search.

        • description: optional string

          Optional description of the custom tool, used to provide more context.

        • format: optional CustomToolInputFormat

          The input format for the custom tool. Default is unconstrained text.

      • Namespace object { description, name, tools, type }

        Groups function/custom tools under a shared namespace.

        • description: string

          A description of the namespace shown to the model.

        • name: string

          The namespace name used in tool calls (for example, crm).

        • tools: array of object { name, type, allowed_callers, 6 more } or object { name, type, allowed_callers, 4 more }

          The function/custom tools available inside this namespace.

          • Function object { name, type, allowed_callers, 6 more }

            • name: string

            • type: "function"

              • "function"

            • allowed_callers: optional array of "direct" or "programmatic" or null

              The tool invocation context(s).

              • "direct"

              • "programmatic"

            • async: optional boolean

              Whether the tool response can be returned asynchronously versus immediately returned on next response creation.

            • defer_loading: optional boolean

              Whether this function should be deferred and discovered via tool search.

            • description: optional string or null

            • output_schema: optional map[unknown] or null

              A JSON Schema describing the JSON value encoded in string outputs for this function tool. This does not describe content-array outputs.

            • parameters: optional unknown or null

            • strict: optional boolean or null

              Whether to enforce strict parameter validation. If omitted, Responses attempts to use strict validation when the schema is compatible, and falls back to non-strict validation otherwise.

          • Custom object { name, type, allowed_callers, 4 more }

            A custom tool that processes input using a specified format. Learn more about custom tools

            • name: string

              The name of the custom tool, used to identify it in tool calls.

            • type: "custom"

              The type of the custom tool. Always custom.

              • "custom"

            • allowed_callers: optional array of "direct" or "programmatic" or null

              The tool invocation context(s).

              • "direct"

              • "programmatic"

            • async: optional boolean

              Whether the tool response can be returned asynchronously versus immediately returned on next response creation.

            • defer_loading: optional boolean

              Whether this tool should be deferred and discovered via tool search.

            • description: optional string

              Optional description of the custom tool, used to provide more context.

            • format: optional CustomToolInputFormat

              The input format for the custom tool. Default is unconstrained text.

        • type: "namespace"

          The type of the tool. Always namespace.

          • "namespace"

      • ToolSearch object { type, description, execution, parameters }

        Hosted or BYOT tool search configuration for deferred tools.

        • type: "tool_search"

          The type of the tool. Always tool_search.

          • "tool_search"

        • description: optional string or null

          Description shown to the model for a client-executed tool search tool.

        • execution: optional "server" or "client"

          Whether tool search is executed by the server or by the client.

          • "server"

          • "client"

        • parameters: optional unknown or null

          Parameter schema for a client-executed tool search tool.

      • WebSearchPreview object { type, search_content_types, search_context_size, user_location }

        This tool searches the web for relevant results to use in a response. Learn more about the web search tool.

        • type: "web_search_preview" or "web_search_preview_2025_03_11"

          The type of the web search tool. One of web_search_preview or web_search_preview_2025_03_11.

          • "web_search_preview"

          • "web_search_preview_2025_03_11"

        • search_content_types: optional array of "text" or "image"

          • "text"

          • "image"

        • search_context_size: optional "low" or "medium" or "high"

          High level guidance for the amount of context window space to use for the search. One of low, medium, or high. medium is the default.

          • "low"

          • "medium"

          • "high"

        • user_location: optional object { type, city, country, 2 more } or null

          The approximate location of the user. If omitted or null, defaults to the United States. To avoid this fallback, pass {"type": "approximate"} without location fields. To localize results, provide the relevant location fields.

          • type: "approximate"

            The type of location approximation. Always approximate.

            • "approximate"

          • city: optional string or null

            Free text input for the city of the user, e.g. San Francisco.

          • country: optional string or null

            The two-letter ISO country code of the user, e.g. US.

          • region: optional string or null

            Free text input for the region of the user, e.g. California.

          • timezone: optional string or null

            The IANA timezone of the user, e.g. America/Los_Angeles.

      • ApplyPatch object { type, allowed_callers }

        Allows the assistant to create, delete, or update files using unified diffs.

        • type: "apply_patch"

          The type of the tool. Always apply_patch.

          • "apply_patch"

        • allowed_callers: optional array of "direct" or "programmatic" or null

          The tool invocation context(s).

          • "direct"

          • "programmatic"

    • type: "additional_tools"

      The item type. Always additional_tools.

      • "additional_tools"

    • id: optional string or null

      The unique ID of this additional tools item.

  • ConfigurationUpdate object { type, id, reasoning }

    An update to the conversation's response configuration. The configuration remains in effect for subsequent responses until it is replaced by another configuration update.

    • type: "configuration_update"

      The item type. Always configuration_update.

      • "configuration_update"

    • id: optional string or null

      The unique ID of the configuration update item.

    • reasoning: optional object { effort }

      Updates to reasoning configuration. Only effort is supported.

      • effort: optional ReasoningEffort or null

        The reasoning effort to use for subsequent responses until another configuration update replaces it.

        • "none"

        • "minimal"

        • "low"

        • "medium"

        • "high"

        • "xhigh"

        • "max"

  • Reasoning object { id, summary, type, 3 more }

    A description of the chain of thought used by a reasoning model while generating a response. Be sure to include these items in your input to the Responses API for subsequent turns of a conversation if you are manually managing context.

    • id: string

      The unique identifier of the reasoning content.

    • summary: array of SummaryTextContent

      Reasoning summary content.

      • text: string

        A summary of the reasoning output from the model so far.

      • type: "summary_text"

        The type of the object. Always summary_text.

        • "summary_text"

    • type: "reasoning"

      The type of the object. Always reasoning.

      • "reasoning"

    • content: optional array of object { text, type }

      Reasoning text content.

      • text: string

        The reasoning text from the model.

      • type: "reasoning_text"

        The type of the reasoning text. Always reasoning_text.

        • "reasoning_text"

    • encrypted_content: optional string or null

      The encrypted content of the reasoning item. This is populated by default for reasoning items returned by POST /v1/responses and WebSocket response.create requests.

      When streaming, use the completed reasoning item and its encrypted_content from the response.output_item.done event in subsequent requests. The encrypted_content in response.output_item.added may be incomplete. This is especially important when store is false or when using Zero Data Retention.

    • status: optional "in_progress" or "completed" or "incomplete"

      The status of the item. One of in_progress, completed, or incomplete. Populated when items are returned via API.

      • "in_progress"

      • "completed"

      • "incomplete"

  • Compaction object { encrypted_content, type, id }

    A compaction item generated by the v1/responses/compact API.

    • encrypted_content: string

      The encrypted content of the compaction summary.

    • type: "compaction"

      The type of the item. Always compaction.

      • "compaction"

    • id: optional string or null

      The ID of the compaction item.

  • ImageGenerationCall object { id, result, status, 7 more }

    An image generation request made by the model.

    • id: string

      The unique ID of the image generation call.

    • result: string or null

      The generated image encoded in base64.

    • status: "in_progress" or "completed" or "generating" or "failed"

      The status of the image generation call.

      • "in_progress"

      • "completed"

      • "generating"

      • "failed"

    • type: "image_generation_call"

      The type of the image generation call. Always image_generation_call.

      • "image_generation_call"

    • action: optional "generate" or "edit" or "auto" or null

      The action used for image generation.

      • "generate"

      • "edit"

      • "auto"

    • background: optional "transparent" or "opaque" or "auto" or null

      The background setting used for generation.

      • "transparent"

      • "opaque"

      • "auto"

    • output_format: optional "png" or "webp" or "jpeg" or null

      The output format used for generation.

      • "png"

      • "webp"

      • "jpeg"

    • quality: optional "low" or "medium" or "high" or 3 more or null

      The quality of the image generated by the image generation tool call. One of low, medium, high, xhigh, max, or auto.

      • "low"

      • "medium"

      • "high"

      • "xhigh"

      • "max"

      • "auto"

    • revised_prompt: optional string or null

      The prompt that was used after any model prompt rewriting.

    • size: optional string or "1024x1024" or "1024x1536" or "1536x1024" or null

      The image dimensions as a WIDTHxHEIGHT string, for example 1536x864.

      • string

      • "1024x1024" or "1024x1536" or "1536x1024"

        The image dimensions as a WIDTHxHEIGHT string, for example 1536x864.

        • "1024x1024"

        • "1024x1536"

        • "1536x1024"

  • CodeInterpreterCall object { id, code, container_id, 3 more }

    A tool call to run code.

    • id: string

      The unique ID of the code interpreter tool call.

    • code: string or null

      The code to run, or null if not available.

    • container_id: string

      The ID of the container used to run the code.

    • outputs: array of object { logs, type } or object { type, url } or null

      The outputs generated by the code interpreter, such as logs or images. Can be null if no outputs are available.

      • Logs object { logs, type }

        The logs output from the code interpreter.

        • logs: string

          The logs output from the code interpreter.

        • type: "logs"

          The type of the output. Always logs.

          • "logs"

      • Image object { type, url }

        The image output from the code interpreter.

        • type: "image"

          The type of the output. Always image.

          • "image"

        • url: string

          The URL of the image output from the code interpreter.

    • status: "in_progress" or "completed" or "incomplete" or 2 more

      The status of the code interpreter tool call. Valid values are in_progress, completed, incomplete, interpreting, and failed.

      • "in_progress"

      • "completed"

      • "incomplete"

      • "interpreting"

      • "failed"

    • type: "code_interpreter_call"

      The type of the code interpreter tool call. Always code_interpreter_call.

      • "code_interpreter_call"

  • LocalShellCall object { id, action, call_id, 2 more }

    A tool call to run a command on the local shell.

    • id: string

      The unique ID of the local shell call.

    • action: object { command, env, type, 3 more }

      Execute a shell command on the server.

      • command: array of string

        The command to run.

      • env: map[string]

        Environment variables to set for the command.

      • type: "exec"

        The type of the local shell action. Always exec.

        • "exec"

      • timeout_ms: optional number or null

        Optional timeout in milliseconds for the command.

      • user: optional string or null

        Optional user to run the command as.

      • working_directory: optional string or null

        Optional working directory to run the command in.

    • call_id: string

      The unique ID of the local shell tool call generated by the model.

    • status: "in_progress" or "completed" or "incomplete"

      The status of the local shell call.

      • "in_progress"

      • "completed"

      • "incomplete"

    • type: "local_shell_call"

      The type of the local shell call. Always local_shell_call.

      • "local_shell_call"

  • LocalShellCallOutput object { id, output, type, status }

    The output of a local shell tool call.

    • id: string

      The unique ID of the local shell tool call generated by the model.

    • output: string

      A JSON string of the output of the local shell tool call.

    • type: "local_shell_call_output"

      The type of the local shell tool call output. Always local_shell_call_output.

      • "local_shell_call_output"

    • status: optional "in_progress" or "completed" or "incomplete" or null

      The status of the item. One of in_progress, completed, or incomplete.

      • "in_progress"

      • "completed"

      • "incomplete"

  • ShellCall object { action, call_id, type, 4 more }

    A tool representing a request to execute one or more shell commands.

    • action: object { commands, max_output_length, timeout_ms }

      The shell commands and limits that describe how to run the tool call.

      • commands: array of string

        Ordered shell commands for the execution environment to run.

      • max_output_length: optional number or null

        Maximum number of UTF-8 characters to capture from combined stdout and stderr output.

      • timeout_ms: optional number or null

        Maximum wall-clock time in milliseconds to allow the shell commands to run.

    • call_id: string

      The unique ID of the shell tool call generated by the model.

    • type: "shell_call"

      The type of the item. Always shell_call.

      • "shell_call"

    • id: optional string or null

      The unique ID of the shell tool call. Populated when this item is returned via API.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          The caller type. Always direct.

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          The caller type. Always program.

          • "program"

    • environment: optional LocalEnvironment or ContainerReference or null

      The environment to execute the shell commands in.

      • LocalEnvironment object { type, skills }

      • ContainerReference object { container_id, type }

    • status: optional "in_progress" or "completed" or "incomplete" or null

      The status of the shell call. One of in_progress, completed, or incomplete.

      • "in_progress"

      • "completed"

      • "incomplete"

  • ShellCallOutput object { call_id, output, type, 4 more }

    The streamed output items emitted by a shell tool call.

    • call_id: string

      The unique ID of the shell tool call generated by the model.

    • output: array of ResponseFunctionShellCallOutputContent

      Captured chunks of stdout and stderr output, along with their associated outcomes.

      • outcome: object { type } or object { exit_code, type }

        The exit or timeout outcome associated with this shell call.

        • Timeout object { type }

          Indicates that the shell call exceeded its configured time limit.

          • type: "timeout"

            The outcome type. Always timeout.

            • "timeout"

        • Exit object { exit_code, type }

          Indicates that the shell commands finished and returned an exit code.

          • exit_code: number

            The exit code returned by the shell process.

          • type: "exit"

            The outcome type. Always exit.

            • "exit"

      • stderr: string

        Captured stderr output for the shell call.

      • stdout: string

        Captured stdout output for the shell call.

    • type: "shell_call_output"

      The type of the item. Always shell_call_output.

      • "shell_call_output"

    • id: optional string or null

      The unique ID of the shell tool call output. Populated when this item is returned via API.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          The caller type. Always direct.

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          The caller type. Always program.

          • "program"

    • max_output_length: optional number or null

      The maximum number of UTF-8 characters captured for this shell call's combined output.

    • status: optional "in_progress" or "completed" or "incomplete" or null

      The status of the shell call output.

      • "in_progress"

      • "completed"

      • "incomplete"

  • ApplyPatchCall object { call_id, operation, status, 3 more }

    A tool call representing a request to create, delete, or update files using diff patches.

    • call_id: string

      The unique ID of the apply patch tool call generated by the model.

    • operation: object { diff, path, type } or object { path, type } or object { diff, path, type }

      The specific create, delete, or update instruction for the apply_patch tool call.

      • CreateFile object { diff, path, type }

        Instruction for creating a new file via the apply_patch tool.

        • diff: string

          Unified diff content to apply when creating the file.

        • path: string

          Path of the file to create relative to the workspace root.

        • type: "create_file"

          The operation type. Always create_file.

          • "create_file"

      • DeleteFile object { path, type }

        Instruction for deleting an existing file via the apply_patch tool.

        • path: string

          Path of the file to delete relative to the workspace root.

        • type: "delete_file"

          The operation type. Always delete_file.

          • "delete_file"

      • UpdateFile object { diff, path, type }

        Instruction for updating an existing file via the apply_patch tool.

        • diff: string

          Unified diff content to apply to the existing file.

        • path: string

          Path of the file to update relative to the workspace root.

        • type: "update_file"

          The operation type. Always update_file.

          • "update_file"

    • status: "in_progress" or "completed"

      The status of the apply patch tool call. One of in_progress or completed.

      • "in_progress"

      • "completed"

    • type: "apply_patch_call"

      The type of the item. Always apply_patch_call.

      • "apply_patch_call"

    • id: optional string or null

      The unique ID of the apply patch tool call. Populated when this item is returned via API.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          The caller type. Always direct.

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          The caller type. Always program.

          • "program"

  • ApplyPatchCallOutput object { call_id, status, type, 3 more }

    The streamed output emitted by an apply patch tool call.

    • call_id: string

      The unique ID of the apply patch tool call generated by the model.

    • status: "completed" or "failed"

      The status of the apply patch tool call output. One of completed or failed.

      • "completed"

      • "failed"

    • type: "apply_patch_call_output"

      The type of the item. Always apply_patch_call_output.

      • "apply_patch_call_output"

    • id: optional string or null

      The unique ID of the apply patch tool call output. Populated when this item is returned via API.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          The caller type. Always direct.

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          The caller type. Always program.

          • "program"

    • output: optional string or null

      Optional human-readable log text from the apply patch tool (e.g., patch results or errors).

  • McpListTools object { id, server_label, tools, 2 more }

    A list of tools available on an MCP server.

    • id: string

      The unique ID of the list.

    • server_label: string

      The label of the MCP server.

    • tools: array of object { input_schema, name, annotations, description }

      The tools available on the server.

      • input_schema: unknown

        The JSON schema describing the tool's input.

      • name: string

        The name of the tool.

      • annotations: optional unknown or null

        Additional annotations about the tool.

      • description: optional string or null

        The description of the tool.

    • type: "mcp_list_tools"

      The type of the item. Always mcp_list_tools.

      • "mcp_list_tools"

    • error: optional string or null

      Error message if the server could not list tools.

  • McpApprovalRequest object { id, arguments, name, 2 more }

    A request for human approval of a tool invocation.

    • id: string

      The unique ID of the approval request.

    • arguments: string

      A JSON string of arguments for the tool.

    • name: string

      The name of the tool to run.

    • server_label: string

      The label of the MCP server making the request.

    • type: "mcp_approval_request"

      The type of the item. Always mcp_approval_request.

      • "mcp_approval_request"

  • McpApprovalResponse object { approval_request_id, approve, type, 2 more }

    A response to an MCP approval request.

    • approval_request_id: string

      The ID of the approval request being answered.

    • approve: boolean

      Whether the request was approved.

    • type: "mcp_approval_response"

      The type of the item. Always mcp_approval_response.

      • "mcp_approval_response"

    • id: optional string or null

      The unique ID of the approval response

    • reason: optional string or null

      Optional reason for the decision.

  • McpCall object { id, arguments, name, 6 more }

    An invocation of a tool on an MCP server.

    • id: string

      The unique ID of the tool call.

    • arguments: string

      A JSON string of the arguments passed to the tool.

    • name: string

      The name of the tool that was run.

    • server_label: string

      The label of the MCP server running the tool.

    • type: "mcp_call"

      The type of the item. Always mcp_call.

      • "mcp_call"

    • approval_request_id: optional string or null

      Unique identifier for the MCP tool call approval request. Include this value in a subsequent mcp_approval_response input to approve or reject the corresponding tool call.

    • error: optional McpToolCallError or null

      The error from the tool call, if any.

      • McpProtocolError object { code, message, type }

        • code: number

        • message: string

        • type: "mcp_protocol_error"

          • "mcp_protocol_error"

      • McpToolExecutionError object { content, type }

        • content: unknown

        • type: "mcp_tool_execution_error"

          • "mcp_tool_execution_error"

      • HTTPError object { code, message, type }

        • code: number

        • message: string

        • type: "http_error"

          • "http_error"

    • output: optional string or null

      The output from the tool call.

    • status: optional "in_progress" or "completed" or "incomplete" or 2 more

      The status of the tool call. One of in_progress, completed, incomplete, calling, or failed.

      • "in_progress"

      • "completed"

      • "incomplete"

      • "calling"

      • "failed"

  • CustomToolCallOutput object { call_id, output, type, 2 more }

    The output of a custom tool call from your code, being sent back to the model.

    • call_id: string

      The call ID, used to map this custom tool call output to a custom tool call.

    • output: string or array of ResponseInputText or ResponseInputImage or ResponseInputFile

      The output from the custom tool call generated by your code. Can be a string or an list of output content.

      • StringOutput = string

        A string of the output of the custom tool call.

      • OutputContentList = array of ResponseInputText or ResponseInputImage or ResponseInputFile

        Text, image, or file output of the custom tool call.

        • ResponseInputText object { text, type, prompt_cache_breakpoint }

          A text input to the model.

        • ResponseInputImage object { detail, type, file_id, 2 more }

          An image input to the model. Learn about image inputs.

        • ResponseInputFile object { type, detail, file_data, 4 more }

          A file input to the model.

    • type: "custom_tool_call_output"

      The type of the custom tool call output. Always custom_tool_call_output.

      • "custom_tool_call_output"

    • id: optional string

      The unique ID of the custom tool call output in the OpenAI platform.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          The caller type. Always direct.

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          The caller type. Always program.

          • "program"

  • CustomToolCall object { call_id, input, name, 5 more }

    A call to a custom tool created by the model.

    • call_id: string

      An identifier used to map this custom tool call to a tool call output.

    • input: string

      The input for the custom tool call generated by the model.

    • name: string

      The name of the custom tool being called.

    • type: "custom_tool_call"

      The type of the custom tool call. Always custom_tool_call.

      • "custom_tool_call"

    • id: optional string

      The unique ID of the custom tool call in the OpenAI platform.

    • async: optional boolean

      Whether the custom tool call runs asynchronously.

    • caller: optional object { type } or object { caller_id, type } or null

      The execution context that produced this tool call.

      • Direct object { type }

        • type: "direct"

          • "direct"

      • Program object { caller_id, type }

        • caller_id: string

          The call ID of the program item that produced this tool call.

        • type: "program"

          • "program"

    • namespace: optional string

      The namespace of the custom tool being called.

  • CompactionTrigger object { type, id }

    Compacts the current context. Must be the final input item.

    • type: "compaction_trigger"

      The type of the item. Always compaction_trigger.

      • "compaction_trigger"

    • id: optional string or null

      The unique ID of this compaction trigger.

  • ItemReference object { id, type }

    An internal identifier for an item to reference.

    • id: string

      The ID of the item to reference.

    • type: optional "item_reference" or null

      The type of item to reference. Always item_reference.

      • "item_reference"

  • Program object { id, call_id, code, 2 more }

    • id: string

      The unique ID of this program item.

    • call_id: string

      The stable call ID of the program item.

    • code: string

      The JavaScript source executed by programmatic tool calling.

    • fingerprint: string

      Opaque program replay fingerprint that must be round-tripped.

    • type: "program"

      The item type. Always program.

      • "program"

  • ProgramOutput object { id, call_id, result, 2 more }

    • id: string

      The unique ID of this program output item.

    • call_id: string

      The call ID of the program item.

    • result: string

      The result produced by the program item.

    • status: "completed" or "incomplete"

      The terminal status of the program output.

      • "completed"

      • "incomplete"

    • type: "program_output"

      The item type. Always program_output.

      • "program_output"

• type: "response.item.create"

  The Live client event type. Always response.item.create.

  • "response.item.create"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "response.item.create",
  "event_id": "evt_item_001",
  "item": {
    "type": "message",
    "role": "user",
    "content": [
      {
        "type": "input_text",
        "text": "Please check for a table for two at 7 PM."
      }
    ]
  }
}

response.create

Request a response from the Live session’s Responses backend, or continue a delegated response waiting for tool results. Requires Responses delegation.

Schema

Schema name: LiveResponseCreateParam

• type: "response.create"

  The Live client event type. Always response.create.

  • "response.create"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "response.create",
  "event_id": "evt_response_001"
}

session.close

Request that the Live session close. The terminal session.closed event contains the close reason and final usage.

Schema

Schema name: LiveSessionCloseParam

• type: "session.close"

  The Live client event type. Always session.close.

  • "session.close"

• event_id: optional string or null

  Optional client identifier for correlating this command with a server event's client_event_id or error.client_event_id.

Example

{
  "type": "session.close",
  "event_id": "evt_close_001"
}

Server events

transport.ringing

The outbound SIP provider leg is ringing or providing early media. Delivered only to sideband observers.

Schema

Schema name: LiveTransportRinging

• event_id: string

• session_id: string

  The canonical Live session ID.

• type: "transport.ringing"

  • "transport.ringing"

Example

{
  "type": "transport.ringing",
  "event_id": "event_call_1",
  "session_id": "live_u0_123"
}

transport.answered

The outbound SIP provider leg answered and media is established. Delivered only to sideband observers.

Schema

Schema name: LiveTransportAnswered

• event_id: string

• session_id: string

  The canonical Live session ID.

• type: "transport.answered"

  • "transport.answered"

Example

{
  "type": "transport.answered",
  "event_id": "event_call_2",
  "session_id": "live_u0_123"
}

transport.failed

An asynchronous outbound SIP setup failure. Delivered only to sideband observers.

Schema

Schema name: LiveTransportFailed

• error: object { code, message, type, param }

  • code: string

    The call setup failure code.

  • message: string

  • type: "call_error"

    • "call_error"

  • param: optional string

    The parameter related to the error, if any. Empty when no parameter applies.

• event_id: string

• session_id: string

  The canonical Live session ID.

• type: "transport.failed"

  • "transport.failed"

Example

{
  "type": "transport.failed",
  "event_id": "event_call_4",
  "session_id": "live_u0_123",
  "error": {
    "type": "call_error",
    "code": "provider_invite_failed",
    "message": "provider rejected the call",
    "param": ""
  }
}

session.started

Returned when a Live session has started. Contains the resolved session configuration, including server defaults.

Schema

Schema name: LiveSessionStarted

• event_id: string

  The unique ID of the Live server event.

• session: SessionResource

  The resolved Live session configuration and server-assigned session metadata.

  • id: string

    The unique ID of the Live session. Use this ID for sideband connections, forking, and recording download.

  • expires_at: number

    The Unix timestamp, in seconds, at which the Live session expires.

  • model: string or "gpt-live-1"

    The Live model. Required in the session configuration for every transport; do not pass it as a URL query parameter.

    • string

    • "gpt-live-1"

      The Live model. Required in the session configuration for every transport; do not pass it as a URL query parameter.

      • "gpt-live-1"

  • status: "active"

    The status of the session snapshot. Always active, including the final snapshot in session.closed; use the event type to determine that the session has closed.

    • "active"

  • audio: optional object { format, output }

    Startup audio configuration. Only primary WebSockets accept audio.format; WebRTC and SIP negotiate their media format. Voice and format are immutable after startup.

    • format: optional AudioFormat

      Audio encoding and sample rate for audio sent and received over a Live WebSocket connection. WebRTC and SIP negotiate their media format separately.

      • AudioPCM object { rate, type }

        Raw, mono 16-bit little-endian PCM audio for a Live WebSocket connection.

        • rate: 16000 or 24000

          Audio sample rate in hertz. Live WebSocket PCM audio supports 16000 or 24000 Hz.

          • 16000

          • 24000

        • type: "audio/pcm"

          The audio encoding. Always audio/pcm.

          • "audio/pcm"

      • AudioPCMU object { rate, type }

        Raw, mono G.711 μ-law audio for a Live WebSocket connection.

        • rate: number

          Audio sample rate in hertz. G.711 audio uses 8000 Hz.

        • type: "audio/pcmu"

          The audio encoding. Always audio/pcmu.

          • "audio/pcmu"

      • AudioPCMA object { rate, type }

        Raw, mono G.711 A-law audio for a Live WebSocket connection.

        • rate: number

          Audio sample rate in hertz. G.711 audio uses 8000 Hz.

        • type: "audio/pcma"

          The audio encoding. Always audio/pcma.

          • "audio/pcma"

    • output: optional object { voice }

      The voice used for speech generated by the Live model.

      • voice: optional string or "alloy" or "ash" or "ballad" or 19 more or CustomVoice

        The voice used for Live speech, as a built-in voice name or a custom voice object containing its ID. Defaults to marin and cannot change after startup.

        • string

        • "alloy" or "ash" or "ballad" or 19 more

          The voice used for Live speech, as a built-in voice name or a custom voice object containing its ID. Defaults to marin and cannot change after startup.

          • "alloy"

          • "ash"

          • "ballad"

          • "beacon"

          • "bossa"

          • "cedar"

          • "cinder"

          • "coral"

          • "delta"

          • "echo"

          • "gleam"

          • "marin"

          • "meridian"

          • "quartz"

          • "ripple"

          • "sage"

          • "shimmer"

          • "stone"

          • "tempo"

          • "verse"

          • "vesper"

          • "willow"

        • CustomVoice object { id }

          • id: string

  • client: optional ClientConfig

    Startup-only capabilities for an untrusted frontend attached to a unified WebRTC session. Trusted sideband connections are unaffected.

    • data_channel: DataChannelConfig

      Client and server event permissions for the WebRTC frontend data channel.

      • allowed_client_events: optional "all" or array of string

        Client event types that the frontend data channel may send. Use 'all' to allow every client event; an empty array allows none. Omission preserves the existing allow-all behavior.

        • "all"

          • "all"

        • array of string

      • allowed_server_events: optional "all" or array of ServerEventSelector

        Server events that may be sent to the frontend data channel. Use 'all' to allow every server event; an empty array allows none. Omission preserves the existing allow-all behavior. Responses events use an object with type 'response.event' and a response_event selector.

        • "all"

          • "all"

        • array of ServerEventSelector

          • type: string

            The outer Live server event type. Use 'response.event' for Responses events.

          • response_event: optional string

            The nested Responses event type. Required when type is 'response.event'; forbidden for other event types.

  • delegation: optional ClientDelegation or object { responses, type } or null

    Who handles tasks delegated by the Live model. Omitted or null selects your application; use responses to let the API manage a Responses backend.

    • ClientDelegation object { type }

      Delegate tasks to your application. The Live session emits delegation events that your backend handles.

      • type: "client"

        The delegation owner. Always client for tasks handled by your application.

        • "client"

    • Responses object { responses, type }

      Delegate tasks to a Responses model managed by the Live session.

      • responses: ResponsesDelegationConfig

        Backend model, prompt, and tools used when the Live session delegates a task to Responses.

        • model: string

          The model used for server-owned Responses delegations.

        • instructions: optional string or null

          Instructions for the delegated Responses model, separate from Live instructions. See backend prompting.

        • max_output_tokens: optional number or null

          Maximum number of output tokens for each delegated response.

        • parallel_tool_calls: optional boolean or null

          Whether the delegated Responses model may request multiple tool calls in a single response.

        • reasoning: optional object { effort, summary } or null

          Reasoning settings passed to each delegated Responses request.

          • effort: optional "none" or "minimal" or "low" or 3 more or null

            How much reasoning effort the delegated Responses model should use. Supported values depend on the backend model.

            • "none"

            • "minimal"

            • "low"

            • "medium"

            • "high"

            • "xhigh"

          • summary: optional "concise" or "detailed" or "auto" or null

            The reasoning summary to request from the delegated Responses model, when supported.

            • "concise"

            • "detailed"

            • "auto"

        • service_tier: optional "auto" or "default" or "fast_tier_temp_pilot" or 3 more or null

          Service tier for delegated Responses requests.

          • "auto"

          • "default"

          • "fast_tier_temp_pilot"

          • "flex"

          • "priority"

          • "ultrafast"

        • text: optional object { verbosity } or null

          Text generation settings passed to each delegated Responses request.

          • verbosity: optional "low" or "medium" or "high" or null

            The amount of detail in text generated by the Responses backend. This does not configure the Live model’s spoken delivery.

            • "low"

            • "medium"

            • "high"

        • tool_choice: optional "auto" or "none" or "required" or object { name, type } or object { name, server_label, type }

          Controls which tool the Responses backend uses when handling a task delegated by the Live model.

          • LiveToolChoiceEnum = "auto" or "none" or "required"

            • "auto"

            • "none"

            • "required"

          • LiveFunctionToolChoiceParam object { name, type }

            • name: string

            • type: "function"

              • "function"

          • LiveMCPToolChoiceParam object { name, server_label, type }

            • name: string

            • server_label: string

            • type: "mcp"

              • "mcp"

        • tools: optional array of FunctionTool or object { type }

          Tools available to the Responses backend while it handles tasks delegated by the Live model.

          • FunctionTool object { name, type, description, 2 more }

            A function tool available to the Responses backend when the Live model delegates a task.

            • name: string

              The name the delegated Responses model uses when calling this function.

            • type: "function"

              The tool type. Always function.

              • "function"

            • description: optional string or null

              What the function does and when the delegated Responses model should call it.

            • parameters: optional map[unknown] or null

              A JSON Schema object describing the arguments accepted by the function.

            • strict: optional boolean or null

              Whether the delegated Responses model must follow the function’s parameter schema exactly.

          • WebSearch object { type }

            A web search tool available to the Live session’s Responses backend.

            • type: "web_search"

              The tool type. Always web_search.

              • "web_search"

      • type: "responses"

        The delegation owner. Always responses for tasks handled by the Responses API.

        • "responses"

  • input: optional array of InitialItem

    Ordered text-only history supplied before startup. Supports developer, user, and assistant messages with one text part each; at most 128 messages and 8,192 rendered tokens in total.

    • Developer object { content, role, id, 2 more }

      A developer message included in the initial text history of a Live session.

      • content: array of object { text, type }

        The message content. Supply exactly one text part for the initial Live conversation history.

        • text: string

          The message text to include in the Live session’s initial conversation history.

        • type: optional "input_text"

          The text content type. Always input_text.

          • "input_text"

      • role: "developer"

        The author of this history message. Always developer.

        • "developer"

      • id: optional string or null

        An optional identifier for the supplied history message. Live uses the message’s role and text to initialize the conversation.

      • status: optional "incomplete" or "completed" or null

        The supplied message’s status. Live uses its text as history and does not resume an incomplete message.

        • "incomplete"

        • "completed"

      • type: optional "message"

        The history item type. Always message.

        • "message"

    • User object { content, role, id, 2 more }

      A user message included in the initial text history of a Live session.

      • content: array of object { text, type }

        The message content. Supply exactly one text part for the initial Live conversation history.

        • text: string

          The message text to include in the Live session’s initial conversation history.

        • type: optional "input_text"

          The text content type. Always input_text.

          • "input_text"

      • role: "user"

        The author of this history message. Always user.

        • "user"

      • id: optional string or null

        An optional identifier for the supplied history message. Live uses the message’s role and text to initialize the conversation.

      • status: optional "incomplete" or "completed" or null

        The supplied message’s status. Live uses its text as history and does not resume an incomplete message.

        • "incomplete"

        • "completed"

      • type: optional "message"

        The history item type. Always message.

        • "message"

    • Assistant object { content, role, id, 2 more }

      An assistant message included in the initial text history of a Live session.

      • content: array of object { text, type } or object { text, type }

        The message content. Supply exactly one text part for the initial Live conversation history.

        • Text object { text, type }

          Assistant text supplied as conversation history when starting a Live session.

          • text: string

            The message text to include in the Live session’s initial conversation history.

          • type: optional "text"

            The text content type. Always text.

            • "text"

        • OutputText object { text, type }

          Assistant output text supplied as conversation history when starting a Live session.

          • text: string

            The message text to include in the Live session’s initial conversation history.

          • type: "output_text"

            The text content type. Always output_text.

            • "output_text"

      • role: "assistant"

        The author of this history message. Always assistant.

        • "assistant"

      • id: optional string or null

        An optional identifier for the supplied history message. Live uses the message’s role and text to initialize the conversation.

      • status: optional "incomplete" or "completed" or null

        The supplied message’s status. Live uses its text as history and does not resume an incomplete message.

        • "incomplete"

        • "completed"

      • type: optional "message"

        The history item type. Always message.

        • "message"

  • instructions: optional string or null

    Frontend instructions for voice, conversation, interruptions, and when to delegate. Start with the Live prompting guide; put business rules and tool workflows in a separate backend prompt. Limited to 16,384 client-supplied tokens. Omitted or blank instructions use server defaults. Immutable after startup.

  • store: optional boolean

    Whether to store the session for later forking and recording download. Defaults to false for new sessions.

• type: "session.started"

  The event type, always session.started.

  • "session.started"

• client_event_id: optional string

  The event_id of the client command associated with this server event, when supplied.

Example

{
  "type": "session.started",
  "event_id": "evt_started_001",
  "client_event_id": "evt_start_001",
  "session": {
    "id": "live_abc123",
    "model": "gpt-live-1",
    "status": "active",
    "expires_at": 1788555600,
    "instructions": "Help the caller plan a restaurant reservation. Confirm details before booking.",
    "input": [],
    "audio": {
      "format": {
        "type": "audio/pcm",
        "rate": 24000
      },
      "output": {
        "voice": "marin"
      }
    },
    "delegation": {
      "type": "client"
    }
  }
}

session.updated

Returned when a Live session update is accepted. Contains the resolved session configuration after the update.

Schema

Schema name: LiveSessionUpdated

• event_id: string

  The unique ID of the Live server event.

• session: SessionResource

  The resolved Live session configuration and server-assigned session metadata.

  • id: string

    The unique ID of the Live session. Use this ID for sideband connections, forking, and recording download.

  • expires_at: number

    The Unix timestamp, in seconds, at which the Live session expires.

  • model: string or "gpt-live-1"

    The Live model. Required in the session configuration for every transport; do not pass it as a URL query parameter.

    • string

    • "gpt-live-1"

      The Live model. Required in the session configuration for every transport; do not pass it as a URL query parameter.

      • "gpt-live-1"

  • status: "active"

    The status of the session snapshot. Always active, including the final snapshot in session.closed; use the event type to determine that the session has closed.

    • "active"

  • audio: optional object { format, output }

    Startup audio configuration. Only primary WebSockets accept audio.format; WebRTC and SIP negotiate their media format. Voice and format are immutable after startup.

    • format: optional AudioFormat

      Audio encoding and sample rate for audio sent and received over a Live WebSocket connection. WebRTC and SIP negotiate their media format separately.

      • AudioPCM object { rate, type }

        Raw, mono 16-bit little-endian PCM audio for a Live WebSocket connection.

        • rate: 16000 or 24000

          Audio sample rate in hertz. Live WebSocket PCM audio supports 16000 or 24000 Hz.

          • 16000

          • 24000

        • type: "audio/pcm"

          The audio encoding. Always audio/pcm.

          • "audio/pcm"

      • AudioPCMU object { rate, type }

        Raw, mono G.711 μ-law audio for a Live WebSocket connection.

        • rate: number

          Audio sample rate in hertz. G.711 audio uses 8000 Hz.

        • type: "audio/pcmu"

          The audio encoding. Always audio/pcmu.

          • "audio/pcmu"

      • AudioPCMA object { rate, type }

        Raw, mono G.711 A-law audio for a Live WebSocket connection.

        • rate: number

          Audio sample rate in hertz. G.711 audio uses 8000 Hz.

        • type: "audio/pcma"

          The audio encoding. Always audio/pcma.

          • "audio/pcma"

    • output: optional object { voice }

      The voice used for speech generated by the Live model.

      • voice: optional string or "alloy" or "ash" or "ballad" or 19 more or CustomVoice

        The voice used for Live speech, as a built-in voice name or a custom voice object containing its ID. Defaults to marin and cannot change after startup.

        • string

        • "alloy" or "ash" or "ballad" or 19 more

          The voice used for Live speech, as a built-in voice name or a custom voice object containing its ID. Defaults to marin and cannot change after startup.

          • "alloy"

          • "ash"

          • "ballad"

          • "beacon"

          • "bossa"

          • "cedar"

          • "cinder"

          • "coral"

          • "delta"

          • "echo"

          • "gleam"

          • "marin"

          • "meridian"

          • "quartz"

          • "ripple"

          • "sage"

          • "shimmer"

          • "stone"

          • "tempo"

          • "verse"

          • "vesper"

          • "willow"

        • CustomVoice object { id }

          • id: string

  • client: optional ClientConfig

    Startup-only capabilities for an untrusted frontend attached to a unified WebRTC session. Trusted sideband connections are unaffected.

    • data_channel: DataChannelConfig

      Client and server event permissions for the WebRTC frontend data channel.

      • allowed_client_events: optional "all" or array of string

        Client event types that the frontend data channel may send. Use 'all' to allow every client event; an empty array allows none. Omission preserves the existing allow-all behavior.

        • "all"

          • "all"

        • array of string

      • allowed_server_events: optional "all" or array of ServerEventSelector

        Server events that may be sent to the frontend data channel. Use 'all' to allow every server event; an empty array allows none. Omission preserves the existing allow-all behavior. Responses events use an object with type 'response.event' and a response_event selector.

        • "all"

          • "all"

        • array of ServerEventSelector

          • type: string

            The outer Live server event type. Use 'response.event' for Responses events.

          • response_event: optional string

            The nested Responses event type. Required when type is 'response.event'; forbidden for other event types.

  • delegation: optional ClientDelegation or object { responses, type } or null

    Who handles tasks delegated by the Live model. Omitted or null selects your application; use responses to let the API manage a Responses backend.

    • ClientDelegation object { type }

      Delegate tasks to your application. The Live session emits delegation events that your backend handles.

      • type: "client"

        The delegation owner. Always client for tasks handled by your application.

        • "client"

    • Responses object { responses, type }

      Delegate tasks to a Responses model managed by the Live session.

      • responses: ResponsesDelegationConfig

        Backend model, prompt, and tools used when the Live session delegates a task to Responses.

        • model: string

          The model used for server-owned Responses delegations.

        • instructions: optional string or null

          Instructions for the delegated Responses model, separate from Live instructions. See backend prompting.

        • max_output_tokens: optional number or null

          Maximum number of output tokens for each delegated response.

        • parallel_tool_calls: optional boolean or null

          Whether the delegated Responses model may request multiple tool calls in a single response.

        • reasoning: optional object { effort, summary } or null

          Reasoning settings passed to each delegated Responses request.

          • effort: optional "none" or "minimal" or "low" or 3 more or null

            How much reasoning effort the delegated Responses model should use. Supported values depend on the backend model.

            • "none"

            • "minimal"

            • "low"

            • "medium"

            • "high"

            • "xhigh"

          • summary: optional "concise" or "detailed" or "auto" or null

            The reasoning summary to request from the delegated Responses model, when supported.

            • "concise"

            • "detailed"

            • "auto"

        • service_tier: optional "auto" or "default" or "fast_tier_temp_pilot" or 3 more or null

          Service tier for delegated Responses requests.

          • "auto"

          • "default"

          • "fast_tier_temp_pilot"

          • "flex"

          • "priority"

          • "ultrafast"

        • text: optional object { verbosity } or null

          Text generation settings passed to each delegated Responses request.

          • verbosity: optional "low" or "medium" or "high" or null

            The amount of detail in text generated by the Responses backend. This does not configure the Live model’s spoken delivery.

            • "low"

            • "medium"

            • "high"

        • tool_choice: optional "auto" or "none" or "required" or object { name, type } or object { name, server_label, type }

          Controls which tool the Responses backend uses when handling a task delegated by the Live model.

          • LiveToolChoiceEnum = "auto" or "none" or "required"

            • "auto"

            • "none"

            • "required"

          • LiveFunctionToolChoiceParam object { name, type }

            • name: string

            • type: "function"

              • "function"

          • LiveMCPToolChoiceParam object { name, server_label, type }

            • name: string

            • server_label: string

            • type: "mcp"

              • "mcp"

        • tools: optional array of FunctionTool or object { type }

          Tools available to the Responses backend while it handles tasks delegated by the Live model.

          • FunctionTool object { name, type, description, 2 more }

            A function tool available to the Responses backend when the Live model delegates a task.

            • name: string

              The name the delegated Responses model uses when calling this function.

            • type: "function"

              The tool type. Always function.

              • "function"

            • description: optional string or null

              What the function does and when the delegated Responses model should call it.

            • parameters: optional map[unknown] or null

              A JSON Schema object describing the arguments accepted by the function.

            • strict: optional boolean or null

              Whether the delegated Responses model must follow the function’s parameter schema exactly.

          • WebSearch object { type }

            A web search tool available to the Live session’s Responses backend.

            • type: "web_search"

              The tool type. Always web_search.

              • "web_search"

      • type: "responses"

        The delegation owner. Always responses for tasks handled by the Responses API.

        • "responses"

  • input: optional array of InitialItem

    Ordered text-only history supplied before startup. Supports developer, user, and assistant messages with one text part each; at most 128 messages and 8,192 rendered tokens in total.

    • Developer object { content, role, id, 2 more }

      A developer message included in the initial text history of a Live session.

      • content: array of object { text, type }

        The message content. Supply exactly one text part for the initial Live conversation history.

        • text: string

          The message text to include in the Live session’s initial conversation history.

        • type: optional "input_text"

          The text content type. Always input_text.

          • "input_text"

      • role: "developer"

        The author of this history message. Always developer.

        • "developer"

      • id: optional string or null

        An optional identifier for the supplied history message. Live uses the message’s role and text to initialize the conversation.

      • status: optional "incomplete" or "completed" or null

        The supplied message’s status. Live uses its text as history and does not resume an incomplete message.

        • "incomplete"

        • "completed"

      • type: optional "message"

        The history item type. Always message.

        • "message"

    • User object { content, role, id, 2 more }

      A user message included in the initial text history of a Live session.

      • content: array of object { text, type }

        The message content. Supply exactly one text part for the initial Live conversation history.

        • text: string

          The message text to include in the Live session’s initial conversation history.

        • type: optional "input_text"

          The text content type. Always input_text.

          • "input_text"

      • role: "user"

        The author of this history message. Always user.

        • "user"

      • id: optional string or null

        An optional identifier for the supplied history message. Live uses the message’s role and text to initialize the conversation.

      • status: optional "incomplete" or "completed" or null

        The supplied message’s status. Live uses its text as history and does not resume an incomplete message.

        • "incomplete"

        • "completed"

      • type: optional "message"

        The history item type. Always message.

        • "message"

    • Assistant object { content, role, id, 2 more }

      An assistant message included in the initial text history of a Live session.

      • content: array of object { text, type } or object { text, type }

        The message content. Supply exactly one text part for the initial Live conversation history.

        • Text object { text, type }

          Assistant text supplied as conversation history when starting a Live session.

          • text: string

            The message text to include in the Live session’s initial conversation history.

          • type: optional "text"

            The text content type. Always text.

            • "text"

        • OutputText object { text, type }

          Assistant output text supplied as conversation history when starting a Live session.

          • text: string

            The message text to include in the Live session’s initial conversation history.

          • type: "output_text"

            The text content type. Always output_text.

            • "output_text"

      • role: "assistant"

        The author of this history message. Always assistant.

        • "assistant"

      • id: optional string or null

        An optional identifier for the supplied history message. Live uses the message’s role and text to initialize the conversation.

      • status: optional "incomplete" or "completed" or null

        The supplied message’s status. Live uses its text as history and does not resume an incomplete message.

        • "incomplete"

        • "completed"

      • type: optional "message"

        The history item type. Always message.

        • "message"

  • instructions: optional string or null

    Frontend instructions for voice, conversation, interruptions, and when to delegate. Start with the Live prompting guide; put business rules and tool workflows in a separate backend prompt. Limited to 16,384 client-supplied tokens. Omitted or blank instructions use server defaults. Immutable after startup.

  • store: optional boolean

    Whether to store the session for later forking and recording download. Defaults to false for new sessions.

• type: "session.updated"

  The event type, always session.updated.

  • "session.updated"

• client_event_id: optional string

  The event_id of the client command associated with this server event, when supplied.