mcp.md Codex Docs, 2026-02-19 20:37 UTC → 2026-03-08 00:35 UTC

1# Model Context Protocol1# Model Context Protocol

2 2 

3Give Codex access to third-party tools and context

4 

5Model Context Protocol (MCP) connects models to tools and context. Use it to give Codex access to third-party documentation, or to let it interact with developer tools like your browser or Figma.3Model Context Protocol (MCP) connects models to tools and context. Use it to give Codex access to third-party documentation, or to let it interact with developer tools like your browser or Figma.

6 4 

7Codex supports MCP servers in both the CLI and the IDE extension.5Codex supports MCP servers in both the CLI and the IDE extension.

77- `enabled_tools` (optional): Tool allow list.75- `enabled_tools` (optional): Tool allow list.

78- `disabled_tools` (optional): Tool deny list (applied after `enabled_tools`).76- `disabled_tools` (optional): Tool deny list (applied after `enabled_tools`).

79 77 

80If your OAuth provider requires a static callback URI, set the top-level `mcp_oauth_callback_port` in `config.toml`. If unset, Codex binds to an ephemeral port.78If your OAuth provider requires a fixed callback port, set the top-level `mcp_oauth_callback_port` in `config.toml`. If unset, Codex binds to an ephemeral port.

79 

80If your MCP OAuth flow must use a specific callback URL (for example, a remote devbox ingress URL or a custom callback path), set `mcp_oauth_callback_url`. Codex uses this value as the OAuth `redirect_uri` while still using `mcp_oauth_callback_port` for the callback listener port. Local callback URLs (for example `localhost`) bind on loopback; non-local callback URLs bind on `0.0.0.0` so the callback can reach the host.

81 81 

82#### config.toml examples82#### config.toml examples

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90MY_ENV_VAR = "MY_ENV_VALUE"90MY_ENV_VAR = "MY_ENV_VALUE"

91```91```

92 92 

93```toml

94# Optional MCP OAuth callback overrides (used by `codex mcp login`)

95mcp_oauth_callback_port = 5555

96mcp_oauth_callback_url = "https://devbox.example.internal/callback"

97```

98 

93```toml99```toml

94[mcp_servers.figma]100[mcp_servers.figma]

95url = "https://mcp.figma.com/mcp"101url = "https://mcp.figma.com/mcp"