config-reference.md Codex Docs, 2026-03-20 00:35 UTC → 2026-04-08 00:40 UTC

46| `experimental_compact_prompt_file` | `string (path)` | Load the compaction prompt override from a file (experimental). |46| `experimental_compact_prompt_file` | `string (path)` | Load the compaction prompt override from a file (experimental). |

47| `experimental_use_unified_exec_tool` | `boolean` | Legacy name for enabling unified exec; prefer `[features].unified_exec` or `codex --enable unified_exec`. |47| `experimental_use_unified_exec_tool` | `boolean` | Legacy name for enabling unified exec; prefer `[features].unified_exec` or `codex --enable unified_exec`. |

48| `features.apps` | `boolean` | Enable ChatGPT Apps/connectors support (experimental). |48| `features.apps` | `boolean` | Enable ChatGPT Apps/connectors support (experimental). |

49| `features.codex_hooks` | `boolean` | Enable lifecycle hooks loaded from `hooks.json` (under development; off by default). |

49| `features.enable_request_compression` | `boolean` | Compress streaming request bodies with zstd when supported (stable; on by default). |50| `features.enable_request_compression` | `boolean` | Compress streaming request bodies with zstd when supported (stable; on by default). |

50| `features.fast_mode` | `boolean` | Enable Fast mode selection and the `service_tier = "fast"` path (stable; on by default). |51| `features.fast_mode` | `boolean` | Enable Fast mode selection and the `service_tier = "fast"` path (stable; on by default). |

51| `features.multi_agent` | `boolean` | Enable multi-agent collaboration tools (`spawn_agent`, `send_input`, `resume_agent`, `wait_agent`, and `close_agent`) (stable; on by default). |52| `features.multi_agent` | `boolean` | Enable multi-agent collaboration tools (`spawn_agent`, `send_input`, `resume_agent`, `wait_agent`, and `close_agent`) (stable; on by default). |

90| `mcp_servers.<id>.startup_timeout_sec` | `number` | Override the default 10s startup timeout for an MCP server. |91| `mcp_servers.<id>.startup_timeout_sec` | `number` | Override the default 10s startup timeout for an MCP server. |

91| `mcp_servers.<id>.tool_timeout_sec` | `number` | Override the default 60s per-tool timeout for an MCP server. |92| `mcp_servers.<id>.tool_timeout_sec` | `number` | Override the default 60s per-tool timeout for an MCP server. |

92| `mcp_servers.<id>.url` | `string` | Endpoint for an MCP streamable HTTP server. |93| `mcp_servers.<id>.url` | `string` | Endpoint for an MCP streamable HTTP server. |

93| `model` | `string` | Model to use (e.g., `gpt-5-codex`). |94| `model` | `string` | Model to use (e.g., `gpt-5.4`). |

94| `model_auto_compact_token_limit` | `number` | Token threshold that triggers automatic history compaction (unset uses model defaults). |95| `model_auto_compact_token_limit` | `number` | Token threshold that triggers automatic history compaction (unset uses model defaults). |

95| `model_catalog_json` | `string (path)` | Optional path to a JSON model catalog loaded on startup. Profile-level `profiles.<name>.model_catalog_json` can override this per profile. |96| `model_catalog_json` | `string (path)` | Optional path to a JSON model catalog loaded on startup. Profile-level `profiles.<name>.model_catalog_json` can override this per profile. |

96| `model_context_window` | `number` | Context window tokens available to the active model. |97| `model_context_window` | `number` | Context window tokens available to the active model. |

645 646 

646Key647Key

647 648 

649`features.codex_hooks`

650 

651Type / Values

652 

653`boolean`

654 

655Details

656 

657Enable lifecycle hooks loaded from `hooks.json` (under development; off by default).

658 

659Key

660 

648`features.enable_request_compression`661`features.enable_request_compression`

649 662 

650Type / Values663Type / Values

1181 1194 

1182Details1195Details

1183 1196 

1184Model to use (e.g., `gpt-5-codex`).1197Model to use (e.g., `gpt-5.4`).

1185 1198 

1186Key1199Key

1187 1200