OpenAI Codex

Connect from OpenAI Codex

Codex CLI supports remote MCP servers over streamable HTTP with custom headers natively via a TOML config file.

Configuration File

Edit or create the Codex config:

• User-global: ~/.codex/config.toml
• Project-scoped: .codex/config.toml (in project root)

Add the following block at the end of the file:

[mcp_servers.Atomicwork]
url = "https://<your-subdomain>.atomicwork.com/mcp"
http_headers = { "Authorization" = "Bearer aw_xxx" }

Verify Connection

codex mcp

Notes

• Project-scoped config requires the project to be trusted by Codex.
• You can set default_tools_approval_mode = "auto" to skip per-tool confirmation prompts.