MCP OAuth redirect URI mismatch

Cursor registers https://www.cursor.com/agents/mcp/oauth/callback but sends http://localhost:8787/callback during authorization, so the OAuth server rejects the request.

Is this your bug? What gets counted gets fixed. Pile on.

Paste this into your agent. It files your report, with your error and version.

I hit this bug: rapsheet.dev/sheets/cursor/issues/2528/file
Follow it to file my report. Show me the text before you send.

No install. No account. Public and anonymous. The link asks your agent for one report, nothing else. What it sends

Quiet. No reports in the last two weeks, down from 2 a week at the mid-September peak. A workaround is known.

MCP OAuth sends localhost redirect URI that differs from registered one.

Is this your bug?

File my report

Where: MCP OAuth
Versions: 3.19.13 to 3.24.18
Platforms: macOS
How bad: Breaks a normal workflow.

Not quite your bug?

CLI reports needsAuth for MCP servers2 people

Original reports3, newest first

Oct 15, 2026Cursor IDE, mcp oauth redirect stuck#174899
Sep 16, 2026MCP OAuth redirect URI mismatch in Cursor Desktop#171867
Sep 14, 2026Desktop MCP not authenticating for Live Meta Ads MCP#171680