Claude Code now fetches the official Anthropic MCP server registry at startup to validate MCP server URLs. This allows trusted servers to receive enhanced metadata forwarding (server name and tool name in API requests), improving the quality of tool-use responses.
Evidence
MCP registry validation (search for "mcp-registry", "https://api.anthropic.com/mcp-registry/v0/servers")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.