# clm_88862CC3B842

subject: OpenAI o1 (/record/openai-o1.md)  
predicate: feature_added  
value: reasoning_effort parameter  
valid_from: 2024-12-17  
valid_to: null  
published: 2024-12-17  
recorded: 2026-11-06  
confidence: 0.70  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-11-06  
cite: AsOf. "OpenAI o1 feature added: reasoning_effort parameter", as of 2024-12-17. Claim clm_88862CC3B842, https://asof.is/claim/clm_88862CC3B842, accessed 2026-11-08. Source: https://developers.openai.com/api/docs/changelog#2024-12-17.  
checked: 2026-11-06 · its source page states the value and the date  

> Added reasoning_effort parameter for o1 models.

What https://developers.openai.com/api/docs/changelog#2024-12-17 says, word for word.

## Sources

- https://developers.openai.com/api/docs/changelog#2024-12-17 (primary, OpenAI (API changelog), published 2024-12-17)

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