Codex CLI MCP Setup: Connect MCP Servers to Codex CLI

What it is

OpenAI's open-source coding agent for the terminal, which can read, modify, and run code in your project.

How MCP works in Codex CLI

Codex CLI is an MCP client. You register servers as TOML tables and it launches them over stdio, or connects to remote Streamable HTTP servers; run /mcp in the TUI to list active servers.

Codex uses TOML, not JSON — each server is its own [mcp_servers.<name>] table. You can also run codex mcp to manage servers.

Config file location

~/.codex/config.toml (or a trusted project .codex/config.toml) adds each server as a [mcp_servers.<name>] TOML table.

Add your first server

A good first server is Playwright MCP — Microsoft's browser automation server. It runs locally over stdio via npx, needs no API key, and gives the agent a real browser to drive. Here is the verified Codex CLI config:

[mcp_servers.playwright]
command = "npx"
args = ["@playwright/mcp@latest"]

Restart or reload Codex CLI after saving, then confirm the server's tools show up. Swap in any other server from the directory using the same structure.

Transports & platforms

FAQ