Codex plugin

The tmphost plugin connects Codex to the tmphost.io MCP server and adds a tmphost skill, so Codex can host files at temporary public URLs when you ask it to share something.

LLM-friendly version (Markdown): https://tmphost.io/docs/plugins/codex.md

Install

Add the marketplace, then the plugin from it:

$ codex plugin marketplace add tmphost/tmphost
$ codex plugin add tmphost@tmphost

The marketplace is the public GitHub repository tmphost/tmphost; its .agents/plugins/marketplace.json lists one plugin, tmphost, from plugin/codex. That folder is a portable Agent Plugins package, the same one built for ChatGPT.

Check the install

$ codex plugin list
$ codex mcp list

The first lists tmphost@tmphost as installed and enabled; the second lists the tmphost server at https://mcp.tmphost.io/mcp, not logged in until the first sign-in.

What it adds

Sign in

The first tool call asks you to sign in with your tmphost.io account. The server answers 401, Codex discovers the OAuth endpoints of app.tmphost.io, registers itself (Dynamic Client Registration) and opens the browser. Sign in or sign up, and Codex keeps the token.

Try it

> Share these files as a static site and send me the URL.

Codex uploads index.html into a new folder, the other files into the same folder by its id, and answers with the folder URL, such as https://k7q2m9xa.file.tmphost.io/. The id and URL here are examples. Later: "Extend my tmphost folder by two more hours."

For large or binary files, Codex does better with the tmphost CLI in its shell: it uploads from disk without passing the bytes through the conversation. See plugin or CLI?

Self-hosted tmphost

Instead of the plugin, add your own server's MCP URL (such as https://mcp.example.com/mcp) to Codex as an MCP server named tmphost.