Checked fact 8258 Oct 2026Agents and apps

OpenAI says cache reuse requires the entire rendered prefix to match. Quote: "Cache reuse requires the entire rendered prefix to match."

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The exact words it rests on

Cache reuse requires the entire rendered prefix to match. If content or a relevant setting changes before a breakpoint, the prefix after that change cannot match the existing cache entry.

What the source said when we opened it, on 8 Oct 2026.

The source

Prompt caching
OpenAI

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Checked

Checked by the notis newsroom on 8 Oct 2026, against the source above.

In the story

How prompt caching bills a repeated prompt start 8 Oct 2026

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In a sentence

“OpenAI says cache reuse requires the entire rendered prefix to match. Quote: "Cache reuse requires the entire rendered prefix to match.".” ai notis, checked 8 Oct 2026. Source: Prompt caching (OpenAI). https://ainotis.com/c/825

As a reference (APA style)

ai notis. (2026, October 8). OpenAI says cache reuse requires the entire rendered prefix to match. Quote: "Cache reuse requires the entire rendered prefix to match." [Checked claim 825]. ai notis. https://ainotis.com/c/825

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