CLI / mcpdo: --oauth-debug to show each OAuth step #2844

Which client?

CLI

The problem

When OAuth fails in the CLI or mcpdo, the user sees only the final error. The web client has a step-by-step OAuth view (discovery, registration, authorization, token exchange); terminal users have nothing comparable, so diagnosing a misconfigured authorization server means re-running in the web client or adding a proxy.

Solution you have in mind (optional)

--oauth-debug (and an mcpdo equivalent) printing each step to stderr: protected-resource and authorization-server metadata URLs and statuses, the registration request/response, the authorization URL, and the token request/response status — with secrets, codes and tokens redacted.

Alternatives or workarounds you have tried

Reproducing the flow in the web client's OAuth view, or running through an intercepting proxy.

Already built it locally?

No response

Before you submit

• I searched existing issues and this is not a duplicate.
• This is a request for the Inspector itself, not for the MCP specification or an SDK.