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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.

2026-10-24-claude-code-mcp-admission-and-retries-change-which-servers-start-and-which-calls-repeat

MCP admission and retries change which servers start and which calls repeat. Version 299 checks policy before dynamically added headless/SDK servers connect and before list/get or subagent paths start blocked servers. It also extends the 2026-07-28 protocol default to cloud/Remote Control connectors without flags. Version 302 tolerates missing resultType, ttlMs or cacheScope from peers negotiating that protocol. Version 305 stops allowedMcpServers filtering managed stdio definitions whose variable substitution occurs only in env: a previously omitted server can start after upgrade. Version 307 retries interrupted HTTP tool calls only when marked read-only or idempotent; 309 prevents a disabled server reconnecting through a prompt.

Channel: tagged-release. Half: both. Date: 2026-10-21.

Operator consequence: Re-audit managed MCP inventories at 305+, using deniedMcpServers for explicit prohibitions instead of depending on an allowlist exclusion that no longer applies. Server authors must state retry safety correctly. The client can remove some reconnection glue, but a transport failure still does not prove that a mutating action did nothing. Test protocol fallback and record remote action IDs before retrying consequential work.

Receipt

Finding metadata

Confidence
high

Run: 2026-10-24-weekly-digest-2026-10-13_2026-10-24-frontier-v0

Finding ID: 2026-10-24-claude-code-mcp-admission-and-retries-change-which-servers-start-and-which-calls-repeat

Profile citations

Source links

Primary links, including exact changelog lines when available.

  1. Claude Code
    github release2026-10-24-claude-code-mcp-admission-and-retries-change-which-servers-start-and-which-calls-repeatanthropics/claude-code / v2.1.299github release2026-10-24-claude-code-mcp-admission-and-retries-change-which-servers-start-and-which-calls-repeatanthropics/claude-code / v2.1.302github release2026-10-24-claude-code-mcp-admission-and-retries-change-which-servers-start-and-which-calls-repeatanthropics/claude-code / v2.1.305github release2026-10-24-claude-code-mcp-admission-and-retries-change-which-servers-start-and-which-calls-repeatanthropics/claude-code / v2.1.307github release2026-10-24-claude-code-mcp-admission-and-retries-change-which-servers-start-and-which-calls-repeatanthropics/claude-code / v2.1.309

Versioned source: run artifact