Anthropic: effort levels no longer breaking prompt cache live on API, Claude Code soon

trq212 · x · 2026-09-03

An Anthropic-affiliated engineer confirmed that effort levels no longer breaking the prompt cache is now live on the API but not yet in Claude Code, expected within a day or so.

He apologized for the gap, saying he was out of office and didn't realize the fix didn't ship with the model launch. For developers relying on prompt caching to cut costs, this means raising effort levels will no longer invalidate the cache and trigger re-billing.

Related event: Anthropic ships new capabilities on API, Claude Code to follow in days(2 posts)→

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