René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Implement SEP-837: Specify OIDC application_type during Dynamic Client Registration","articleBody":"This issue tracks implementing [SEP-837](https://github.com/modelcontextprotocol/modelcontextprotocol/pull/837) in the client OAuth flow.\n\nSEP-837 requires MCP clients to specify an `application_type` during OIDC Dynamic Client Registration. When it is omitted, OIDC-compliant authorization servers default the client to `\"web\"`, which conflicts with the loopback (`localhost`, `127.0.0.1`, `::1`) redirect URIs that native clients (CLI and desktop apps) use, so the server can reject the registration.\n\nCurrently `OAuthClientMetadata` has no `application_type` field and `create_client_registration_request` never sends one, so the client hits exactly this default.\n\nSpec: [Application Type and Redirect URI Constraints](https://github.com/modelcontextprotocol/modelcontextprotocol/blob/7df71535a0c9b2057d73966bb6b123e684a940cd/docs/specification/draft/basic/authorization/client-registration.mdx#L152-L179)\n","author":{"url":"https://github.com/stefanoamorelli","@type":"Person","name":"stefanoamorelli"},"datePublished":"2026-06-05T11:17:53.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":1},"url":"https://github.com/2783/python-sdk/issues/2783"}