Under the hoodTier: how much it should matter to you
1Useful: my rating, 1 to 5
1Signal: worth watching, 1 to 5
MCPArea: what it touches
Internal ChangesKind: in v2.1.277,
Internal ChangesSection of the release
What
When Claude Code makes an MCP (Model Context Protocol) tool call, it now prefers to use the tool-use id already attached to the call record, rather than deriving one from request headers as it did before. It also now adds a new per-request metadata header carrying the request id, in addition to the existing claudecode/toolUseId metadata.
Why
This is an internal correctness and traceability improvement for how MCP tool calls are identified, which can help with matching requests to responses correctly and debugging.
