Evidence record / claude-code
A dated record of one change, kept so the writing that cites it can be checked. Compiled from the sources listed below by the research run, not written for reading. The judgment lives in the issues that cite it, below.
2026-10-13-claude-code-local-mcp-connections-negotiate-protocol-2026-07-28-by-default-on-latest
Local MCP connections negotiate protocol 2026-07-28 by default on latest. Local MCP negotiation of this protocol version no longer depends on provider or a flag fetch. The same default reaches claude.ai connectors without flag fetching in 2.1.295. This establishes negotiation, not which additional protocol features any server implements.
Channel: tagged-release (latest only; stable 2.1.287 lacks both). Half: capability. Date: 2026-10-06 (2.1.292), 2026-10-08 (2.1.295).
Operator consequence: Re-test local MCP servers and connector handshakes before moving from stable to latest. Use MCP_PROTOCOL_NEGOTIATION=legacy as the documented compatibility fallback while fixing a server. Do not equate negotiation with a new server capability.
Receipt
Finding metadata
Run: 2026-10-13-profile-refresh-2026-09-21_2026-10-13-frontier-v0
Finding ID: 2026-10-13-claude-code-local-mcp-connections-negotiate-protocol-2026-07-28-by-default-on-latest
Profile citations
- Claude Code / claim / mcp-negotiation-default
- Claude Code / posture / capability
Source links
Primary links, including exact changelog lines when available.
- tagged commit file2026-10-13-claude-code-local-mcp-connections-negotiate-protocol-2026-07-28-by-default-on-latestanthropics/claude-code / CHANGELOG.md#L368tagged commit file2026-10-13-claude-code-local-mcp-connections-negotiate-protocol-2026-07-28-by-default-on-latestanthropics/claude-code / CHANGELOG.md#L202
Versioned source: run artifact