Hi @rem.y,
Thanks for the detailed report with the side-by-side logs. You’re right – this is a confirmed regression in Cursor 3. We’ve flagged it for the team.
Unfortunately, there’s no client-side workaround right now. If your server can be configured to accept requests without the trailing slash (e.g., adding a route alias or disabling redirect-on-missing-slash), that would work around it.
Your hunch about a connection to the Atlassian MCP OAuth 404 thread is reasonable if those endpoints also require trailing slashes.
We’ll update here when this is resolved.