config-basic.md Codex Docs, 2026-02-19 20:53 UTC → 2026-04-29 00:50 UTC

1# Config basics1# Config basics

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3Codex reads configuration details from more than one location. Your personal defaults live in `~/.codex/config.toml`, and you can add project overrides with `.codex/config.toml` files. For security, Codex loads project config files only when you trust the project.3Codex reads configuration details from more than one location. Your personal defaults live in `~/.codex/config.toml`, and you can add project overrides with `.codex/config.toml` files. For security, Codex loads project `.codex/` layers only when you trust the project.

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5## Codex configuration file5## Codex configuration file

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11The CLI and IDE extension share the same configuration layers. You can use them to:11The CLI and IDE extension share the same configuration layers. You can use them to:

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13- Set the default model and provider.13- Set the default model and provider.

14- Configure [approval policies and sandbox settings](https://developers.openai.com/codex/security).14- Configure [approval policies and sandbox settings](https://developers.openai.com/codex/agent-approvals-security#sandbox-and-approvals).

15- Configure [MCP servers](https://developers.openai.com/codex/mcp).15- Configure [MCP servers](https://developers.openai.com/codex/mcp).

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17## Configuration precedence17## Configuration precedence

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28Use that precedence to set shared defaults at the top level and keep profiles focused on the values that differ.28Use that precedence to set shared defaults at the top level and keep profiles focused on the values that differ.

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30If you mark a project as untrusted, Codex skips project-scoped `.codex/` layers (including `.codex/config.toml`) and falls back to user, system, and built-in defaults.30If you mark a project as untrusted, Codex skips project-scoped `.codex/` layers, including project-local config, hooks, and rules. User and system config still load, including user/global hooks and rules.

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32For one-off overrides via `-c`/`--config` (including TOML quoting rules), see [Advanced Config](https://developers.openai.com/codex/config-advanced#one-off-overrides-from-the-cli).32For one-off overrides via `-c`/`--config` (including TOML quoting rules), see [Advanced Config](https://developers.openai.com/codex/config-advanced#one-off-overrides-from-the-cli).

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34On managed machines, your organization may also enforce constraints via34On managed machines, your organization may also enforce constraints via

35 `requirements.toml` (for example, disallowing `approval_policy = "never"` or35 `requirements.toml` (for example, disallowing `approval_policy = "never"` or

36`sandbox_mode = "danger-full-access"`). See [Security](https://developers.openai.com/codex/security).36 `sandbox_mode = "danger-full-access"`). See [Managed

37 configuration](https://developers.openai.com/codex/enterprise/managed-configuration) and [Admin-enforced

38 requirements](https://developers.openai.com/codex/enterprise/managed-configuration#admin-enforced-requirements-requirementstoml).

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38## Common configuration options40## Common configuration options

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44Choose the model Codex uses by default in the CLI and IDE.46Choose the model Codex uses by default in the CLI and IDE.

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46```toml48```toml

47model = "gpt-5.2"49model = "gpt-5.5"

48```50```

49 51 

50#### Approval prompts52#### Approval prompts

55approval_policy = "on-request"57approval_policy = "on-request"

56```58```

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60For behavior differences between `untrusted`, `on-request`, and `never`, see [Run without approval prompts](https://developers.openai.com/codex/agent-approvals-security#run-without-approval-prompts) and [Common sandbox and approval combinations](https://developers.openai.com/codex/agent-approvals-security#common-sandbox-and-approval-combinations).

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58#### Sandbox level62#### Sandbox level

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60Adjust how much filesystem and network access Codex has while executing commands.64Adjust how much filesystem and network access Codex has while executing commands.

63sandbox_mode = "workspace-write"67sandbox_mode = "workspace-write"

64```68```

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70For mode-by-mode behavior (including protected `.git`/`.codex` paths and network defaults), see [Sandbox and approvals](https://developers.openai.com/codex/agent-approvals-security#sandbox-and-approvals), [Protected paths in writable roots](https://developers.openai.com/codex/agent-approvals-security#protected-paths-in-writable-roots), and [Network access](https://developers.openai.com/codex/agent-approvals-security#network-access).

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72#### Windows sandbox mode

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74When running Codex natively on Windows, set the native sandbox mode to `elevated` in the `windows` table. Use `unelevated` only if you don't have administrator permissions or if elevated setup fails.

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76```toml

77[windows]

78sandbox = "elevated" # Recommended

79# sandbox = "unelevated" # Fallback if admin permissions/setup are unavailable

80```

81 

66#### Web search mode82#### Web search mode

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68Codex enables web search by default for local tasks and serves results from a web search cache. The cache is an OpenAI-maintained index of web results, so cached mode returns pre-indexed results instead of fetching live pages. This reduces exposure to prompt injection from arbitrary live content, but you should still treat web results as untrusted. If you are using `--yolo` or another [full access sandbox setting](https://developers.openai.com/codex/security), web search defaults to live results. Choose a mode with `web_search`:84Codex enables web search by default for local tasks and serves results from a web search cache. The cache is an OpenAI-maintained index of web results, so cached mode returns pre-indexed results instead of fetching live pages. This reduces exposure to prompt injection from arbitrary live content, but you should still treat web results as untrusted. If you are using `--yolo` or another [full access sandbox setting](https://developers.openai.com/codex/agent-approvals-security#common-sandbox-and-approval-combinations), web search defaults to live results. Choose a mode with `web_search`:

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70- `"cached"` (default) serves results from the web search cache.86- `"cached"` (default) serves results from the web search cache.

71- `"live"` fetches the most recent data from the web (same as `--search`).87- `"live"` fetches the most recent data from the web (same as `--search`).

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132| Key | Default | Maturity | Description |148| Key | Default | Maturity | Description |

133| -------------------- | :-------------------: | ------------ | ---------------------------------------------------------------------------------------- |149| -------------------- | :-------------------: | ------------ | ---------------------------------------------------------------------------------------- |

134| `apply_patch_freeform` | false | Experimental | Include the freeform `apply_patch` tool |

135| `apps` | false | Experimental | Enable ChatGPT Apps/connectors support |150| `apps` | false | Experimental | Enable ChatGPT Apps/connectors support |

136| `apps_mcp_gateway` | false | Experimental | Route Apps MCP calls through `https://api.openai.com/v1/connectors/mcp/` instead of legacy routing |151| `codex_hooks` | true | Stable | Enable lifecycle hooks from `hooks.json` or inline `[hooks]`. See [Hooks](https://developers.openai.com/codex/hooks). |

137| `elevated_windows_sandbox` | false | Experimental | Use the elevated Windows sandbox pipeline |152| `fast_mode` | true | Stable | Enable Fast mode selection and the `service_tier = "fast"` path |

138| `collaboration_modes` | true | Stable | Enable collaboration modes such as plan mode |153| `memories` | false | Stable | Enable [Memories](https://developers.openai.com/codex/memories) |

139| `experimental_windows_sandbox` | false | Experimental | Use the Windows restricted-token sandbox |154| `multi_agent` | true | Stable | Enable subagent collaboration tools |

140| `multi_agent` | false | Experimental | Enable multi-agent collaboration tools |

141| `personality` | true | Stable | Enable personality selection controls |155| `personality` | true | Stable | Enable personality selection controls |

142| `remote_models` | false | Experimental | Refresh remote model list before showing readiness |156| `shell_snapshot` | true | Stable | Snapshot your shell environment to speed up repeated commands |

143| `runtime_metrics` | false | Experimental | Show runtime metrics summaries in TUI turn separators |

144| `request_rule` | true | Stable | Enable Smart approvals (`prefix_rule` suggestions) |

145| `search_tool` | false | Experimental | Enable `search_tool_bm25` so Codex discovers Apps MCP tools via search before tool calls |

146| `shell_snapshot` | false | Beta | Snapshot your shell environment to speed up repeated commands |

147| `shell_tool` | true | Stable | Enable the default `shell` tool |157| `shell_tool` | true | Stable | Enable the default `shell` tool |

148| `use_linux_sandbox_bwrap` | false | Experimental | Use the bubblewrap-based Linux sandbox pipeline |158| `unified_exec` | `true` except Windows | Stable | Use the unified PTY-backed exec tool |

149| `unified_exec` | false | Beta | Use the unified PTY-backed exec tool |159| `undo` | false | Stable | Enable undo via per-turn git ghost snapshots |

150| `undo` | true | Stable | Enable undo via per-turn git ghost snapshots |

151| `web_search` | true | Deprecated | Legacy toggle; prefer the top-level `web_search` setting |160| `web_search` | true | Deprecated | Legacy toggle; prefer the top-level `web_search` setting |

152| `web_search_cached` | true | Deprecated | Legacy toggle that maps to `web_search = "cached"` when unset |161| `web_search_cached` | false | Deprecated | Legacy toggle that maps to `web_search = "cached"` when unset |

153| `web_search_request` | true | Deprecated | Legacy toggle that maps to `web_search = "live"` when unset |162| `web_search_request` | false | Deprecated | Legacy toggle that maps to `web_search = "live"` when unset |

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155The Maturity column uses feature maturity labels such as Experimental, Beta,164The Maturity column uses feature maturity labels such as Experimental, Beta,

156 and Stable. See [Feature Maturity](https://developers.openai.com/codex/feature-maturity) for how to165 and Stable. See [Feature Maturity](https://developers.openai.com/codex/feature-maturity) for how to

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159Omit feature keys to keep their defaults.168Omit feature keys to keep their defaults.

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170For the current lifecycle hooks MVP, see [Hooks](https://developers.openai.com/codex/hooks).

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161### Enabling features172### Enabling features

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163- In `config.toml`, add `feature_name = true` under `[features]`.174- In `config.toml`, add `feature_name = true` under `[features]`.