Codex mobile in ChatGPT iPhone app cannot use custom plugins or third-party skills

Open 💬 0 comments Opened May 15, 2026 by hacksurvivor

Summary

Codex on iPhone inside the ChatGPT app does not appear to support user-added custom plugins or third-party custom skills. This is a mobile-surface parity problem for users who rely on Codex plugins/skills in Desktop or CLI workflows.

Affected surface

  • ChatGPT app on iPhone
  • Codex mobile / remote Codex experience inside the ChatGPT app

Observed behavior

  • There is no visible way in the iPhone ChatGPT app Codex UI to use custom plugins that the user has added from a third party.
  • There is also no clear UI path for custom skills added from third-party sources.
  • Skills appear to be partially reachable only if the user manually types a $ skill mention, but this is not discoverable and does not solve custom plugin access.

Expected behavior

The iPhone ChatGPT app Codex surface should have parity with the user's enabled Codex environment:

  • Custom / third-party plugins installed or enabled for Codex should be visible and invokable from the mobile Codex UI.
  • Custom / third-party skills should be discoverable from the mobile UI, not only available through manual $ syntax if the user already knows the skill name.
  • If mobile intentionally does not support a class of plugin or skill, the UI should show a clear limitation instead of silently omitting it.

Why this matters

Codex mobile is useful for continuing or controlling desktop work from an iPhone. But many real Codex workflows depend on user-added plugins and custom skills. If those are unavailable on mobile, the same Codex task can behave differently depending on whether the user opens it from Desktop/CLI or from the ChatGPT iPhone app.

Related / adjacent issues

  • #13174 asks for adding external skill repositories in the Codex App.
  • #22752 reports a plugin-loading issue where $ skills still show correctly.

This issue is specifically about the iPhone ChatGPT app / Codex mobile surface and the inability to use user-added custom plugins and third-party skills there.

View original on GitHub ↗