Under the hoodTier: how much it should matter to you
1Useful: my rating, 1 to 5
0Signal: worth watching, 1 to 5
MCPArea: what it touches
Internal ChangesKind: in v2.1.315,
Internal ChangesSection of the release
What
When Claude Code fills in environment variables in headers for MCP and remote connections, it now does the setup only for header values that contain ${, instead of on every call.
Why
Header processing does less work, and the headers that come out are the same.
