#34771 [Bug]: CP OAuth DCR relay returns LiteLLM's own /callback as the client's redirect_uri, causing a self-redirect loop. Reopen for #33699
### Check for existing issues
- [x] I have searched the existing issues and checked that my issue is not a duplicate.
### What happened?
The ticket https://github.com/BerriAI/litellm/issues/33699 currently marked as completed, is still not properly fixed.
Testing on litellm-database:v1.95.0-dev.1 and v1.95.0-dev.2 I can see that the behavior is still there.
The latest logs are below.
Just a side note: from what I can see, some of the changes pushed with the PR related to #33699 , are not visible in the latest code version.
### Steps to Reproduce
1. Register an MCP server in LiteLLM pointed at an upstream that supports OAuth 2.1 with real Dynamic Client Registration and no admin-configured static client_id/client_secret, such as Atlassian's Rovo MCP server 2. Connect to that server from an OAuth 2.1 DCR-compliant MCP client that performs /register before /authorize and reuses the registration response's redirect_uris on /authorize (Open WebUI's native MCP External Tools with Auth: OAuth 2.1 (DCR) does this) 3. Complete the browser consent
Expected: the browser lands on the MCP client's own redirect endpoint with the final code/state, and the client completes its toke…