Sweep 19 Sep 2026 · 02:36Z Build v2.1.278 500 read Stable v2.1.267 Latest v2.1.278 Next v2.1.278 Feeds RSS JSON llms.txt Unofficial
Claude Code v2.1.257 ·

Deferred/lazy tool schemas: new discovery hint text

New hint text explains that deferred tools have no schema yet and must be fetched before they can be called.

TierYou'll noticehow much it should matter to you
Useful2my rating, 1 to 5
Signal2worth watching, 1 to 5
AreaToolswhat it touches
KindImprovementsin v2.1.257,
You'll notice

New hint text explains that deferred tools have no schema yet and must be fetched before they can be called.

New hint text explains deferred/lazy tool schemas: tools listed but not yet loaded have schemas that are NOT available, and calling them directly fails with InputValidationError. Their schemas must be requested via a discovery tool first, distinguishing them from tools that just became available and are ready to use immediately.

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Names in the bundleInputValidationError

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