Cursor/Grok Bot marketplace plugin: Authenticate fails with "Github didn't provide a sign-in link"

[jsolly]

Summary

In Cursor / Grok Bot, the official GitHub marketplace MCP plugin fails OAuth: account stays Needs auth, and clicking Authenticate shows toast "Github didn't provide a sign-in link" (no browser / no authorize URL).

Environment

• Grok Bot desktop 0.44.0 stable, darwin arm64
• Cursor IDE 3.19.13 arm64 (dd066f332fcea7382764400fde902f61920648d0)
• Marketplace plugin id 48677658 (remote MCP user-Github: needsAuth / authentication_required)

Steps

1. Install/open GitHub plugin in Grok Bot desktop Plugins.
2. Account default shows Needs auth.
3. Click Authenticate.
4. Toast: Github didn't provide a sign-in link; still Needs auth.

Expected

Authenticate should return an OAuth authorization URL / open the GitHub sign-in flow.

Notes

• Related Cursor forum (screenshot): https://forum.cursor.com/t/grok-bot-github-plugin-authenticate-github-didnt-provide-a-sign-in-link/170898
• Related-but-distinct Cursor IDE OAuth UX thread: https://forum.cursor.com/t/plugin-mcp-oauth-never-reaches-needsauth-authenticate-button-missing-browser-never-opens/170058
• Local workaround: PAT-backed custom MCP (github-local); marketplace OAuth path still broken.

Happy to provide more client logs if useful.

[laxanarana1513]

I can work on this.

[SamMorrowDrums]

official GitHub marketplace MCP

I am not sure there is an official one that we created. Our auth server doesn't currently support CIMD or DCR so auth requires a pre-provided app currently and that's maybe the issue?

[jsolly]

Thanks @SamMorrowDrums — helpful clarification.

To pin the packaging: this is the Cursor / Grok Bot marketplace GitHub plugin (id 48677658, remote MCP server user-Github), not something we assumed GitHub itself published to that marketplace. On Authenticate it stays Needs auth and toasts "Github didn't provide a sign-in link" (no browser / authorize URL) on Grok Bot desktop 0.44.0 and Cursor IDE 3.19.13.

That lines up with what you described if the auth path expects CIMD/DCR and the server only supports a pre-provided app. Cursor support has already passed the same repro to a teammate on their side (ticket T-F57077 / forum https://forum.cursor.com/t/grok-bot-github-plugin-authenticate-github-didnt-provide-a-sign-in-link/170898); we'll update this thread when they respond. Workaround for now remains a PAT-backed custom MCP (github-local).

• John's AI Assistant

[jsolly]

Update (2026-09-08): After uninstall + retry Authenticate on the Cursor/Grok Bot marketplace GitHub plugin (id 48677658), the toast changed from "Github didn't provide a sign-in link" to:

Couldn't start sign-in for GitHub. Details: fetch failed

Account still Needs auth; no browser / authorize URL. Confirmed on Grok Bot desktop 0.44.0 stable darwin. Conversation ID 2d28dc6b-2e68-43b1-8974-cf75a08ad260. Settings email github@jsolly.com. Forum: https://forum.cursor.com/t/grok-bot-github-plugin-authenticate-github-didnt-provide-a-sign-in-link/170898 . Cursor ticket T-F57077. Workaround remains PAT-backed github-local.

- John's AI Assistant