Codex

Codex reads AGENTS.md, so it picks up GoBanana’s scoped AGENTS.md section on its own after a hand-off. The Codex CLI, the IDE extension and the desktop app share one MCP configuration, so one setup covers all three.

1. Add the server. Pick one:

   CLI

   codex mcp add gobanana --url https://gobanana.fun/api/mcp

   It prints Added global MCP server 'gobanana'.

   config.toml

   Add this to ~/.codex/config.toml (or a trusted project’s .codex/config.toml):

   ~/.codex/config.toml

   [mcp_servers.gobanana]
   url = "https://gobanana.fun/api/mcp"

   IDE or desktop app
   • IDE extension: gear menu, MCP servers, Add server, choose Streamable HTTP, enter the URL, save, then Restart extension.
   • Desktop app: Settings, MCP servers, Add server, choose Streamable HTTP, enter the URL, save, then Restart.

   When GoBanana needs sign in, select Authenticate.

2. Log in:

   codex mcp login gobanana

   Your browser opens the GoBanana sign in page. Codex picks the OAuth client method on its own; do not pass --oauth-client-id.

3. Check it is listed:

   codex mcp list

4. Start Codex and ask: “Use the GoBanana ping tool.”

Older Codex CLIs

With Codex CLI 0.101.0, codex mcp list showed the Auth column as Unsupported for GoBanana right after add, and add did not start a sign in by itself. Run codex mcp login gobanana anyway: it starts the browser sign in. Updating Codex is the better fix.

To sign out, run codex mcp logout gobanana. codex mcp --help lists every MCP command.

Without skills

Codex does not load Claude plugins. Paste the one line from No plugin?, or put it in your AGENTS.md outside the GoBanana markers.

Hand off for Codex

Ask “hand this off”. The agent exports agents_md (Pro) and merges one section into AGENTS.md between <!-- gobanana:<slug> --> markers, never touching the rest. On Free, use BUILD-PROMPT.md. See Hand off.

What was verified

Checked on 2026-10-12 against OpenAI’s Codex MCP docs. On this machine, Codex CLI 0.101.0 with a temporary CODEX_HOME ran the add command above, wrote exactly the config.toml entry shown, and codex mcp list listed it as enabled. codex mcp login gobanana started without error and waited for the browser; the sign in was not completed for these docs.