I vibe-coded up a quick UI for exploring this: https://tools.simonwillison.net/prompt-caching https://tools.simonwillison.net/prompt-caching As far as I can te

I vibe-coded up a quick UI for exploring this: https://tools.simonwillison.net/prompt-caching https://tools.simonwillison.net/prompt-caching As far as I can tell it will indeed reuse the cache up to the point, so this works: Prompt A + B + C - uncached Prompt A + B + D - uses cache for A + B Prompt A + E - uses cache for A