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Claude Code v2.1.274 ·

Strict tool-result pairing mode gated by client launch option, not a simple flag

Strict tool-result pairing mode is now controlled by the client's launch options, not an experiment gate

TierUnder the hoodhow much it should matter to you
Useful2my rating, 1 to 5
Signal2worth watching, 1 to 5
AreaTool Usewhat it touches
KindInternal Changesin v2.1.274,
Under the hood No documentation found

Strict tool-result pairing mode is now controlled by the client's launch options, not an experiment gate

What

The setting that decides whether Claude Code throws an error (instead of silently repairing) when tool calls and their results don't line up correctly has moved to a different check. It's now read from host.launchOptions.strictToolResultPairing(), a value the client application provides at launch, rather than from an internal experiment flag.

Why

This puts control of strict pairing behavior in the hands of whatever application is embedding Claude Code, rather than in a centrally managed experiment.

Read from
Names in the bundlestrictToolResultPairing

See this entry in the whole of v2.1.274 →