Fix Zoom plugin OAuth error 4700 (localhost redirect) in Grok Bot

When you connect the catalog Zoom plugin in Grok Bot, OAuth can open with redirect_uri=http://localhost:8787/callback. Zoom rejects the hostname localhost with error 4700 (invalid redirect). Zoom Marketplace will not let you allowlist localhost; it accepts loopback as http://127.0.0.1 / http://[::1], or HTTPS otherwise.

Cursor staff (deanrie, Aug–Sep 2026) confirmed the diagnosis: Grok Bot hardcodes that localhost callback, the redirect has no setting in the app, and there is no user workaround right now. Recreating your Zoom Marketplace app will not change the callback Cursor sends.

Confirm you hit this bug

1. Open Grok Bot Settings → Plugins.
2. Install or open the catalog Zoom plugin.
3. Start authentication.
4. Zoom shows error 4700 / invalid redirect, or Marketplace refuses localhost on the allow list.

If that matches, stop recreating Zoom OAuth apps — Cursor still sends localhost.

What does not work today

1. Changing a redirect URI inside Grok Bot (no control exists).
2. Recreating the Zoom Marketplace app with a different allow list while Cursor still sends localhost.
3. Treating this as the same bug as Fix custom MCP OAuth redirect_uri failures in Grok Bot or Fix Grok Bot X plugin OAuth when access fails — those are different redirect paths.

What staff are tracking

Staff said they are looking at a Zoom-accepted redirect such as http://127.0.0.1:8787/callback (and reporters also noted Cursor’s agents HTTPS callback https://www.cursor.com/agents/mcp/oauth/callback works for other agent surfaces). No timeline was published as of the Sep 4 bump. Watch the forum thread for the staff update.

Meanwhile

1. Keep Zoom work on a surface where OAuth already succeeds for your account, if you have one.
2. For catalog plugins that do authenticate, official troubleshooting still applies: reopen the plugin detail, complete browser auth, return to Grok Bot, retry; remove and reconnect if the source revoked access.
3. Do not paste Zoom client secrets into ordinary chat.

Pitfalls

• Error 4700 here is a product redirect bug, not “you picked the wrong Zoom plan.”
• A working Zoom login in a normal browser does not prove the Grok Bot catalog plugin can finish OAuth.
• When staff ships a new redirect, reinstall or re-auth the Zoom plugin once; old failed attempts do not auto-heal.