You'll noticeTier: how much it should matter to you
2Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
MCPArea: what it touches
Bug FixesKind: in v2.1.265,
Bug FixesSection of the release
What
For MCP servers (external tools Claude Code connects to) that use the older HTTP+SSE connection method rather than newer transports, Claude Code now checks whether a 401 "unauthorized" response on the connection request really means the server wants OAuth login. If the server's earlier setup request didn't return a 405 "method not allowed" response, the 401 is treated as a genuine OAuth prompt. If it did return 405, Claude Code now refuses to start an OAuth flow at all.
Why
This avoids incorrectly launching an OAuth sign-in flow against MCP servers that don't actually require one, which previously could have interrupted the user with an unnecessary login prompt.
