# clm_DE2168A0EF8E

subject: OpenAI (/record/openai.md)  
predicate: feature_added  
value: 12-hour prompt caching  
valid_from: 2026-10-20  
valid_to: null  
published: 2026-10-20  
recorded: 2026-10-31  
confidence: 0.70  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-10-31  
checked: 2026-10-31 · its source page states the value and the date  

> Oct 20 Feature v1/responses You can now choose 12-hour prompt caching in the API.

What https://developers.openai.com/api/docs/changelog#2026-10-20 says, word for word.

## Sources

- https://developers.openai.com/api/docs/changelog#2026-10-20 (primary, OpenAI, published 2026-10-20)

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