Codex MCP setup: add a remote MCP server to the Codex CLI and IDE extension

Unif API published a guide to connecting MCP servers to Codex, using its own server as the example. It covers the CLI and IDE extension, which share ~/.codex/config.toml.

The guide walks through codex mcp add, remote and local server configuration, OAuth login and checking that tools load. Unif API recommends OAuth for its read-only token.

Browsing Unif API's catalog is free. Calls to call_api are billed per public-data record in workspace credits at $0.001 each, with higher floors listed in the catalog. A new workspace needs a top-up before using call_api; model tokens stay on your OpenAI plan.