# clm_E25E4DA5DE4D

subject: Claude (/record/claude.md)  
predicate: feature_added  
value: mid-conversation system message  
valid_from: 2026-09-22  
valid_to: null  
published: 2026-09-22  
recorded: 2026-11-07  
confidence: 0.70  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-11-07  
cite: AsOf. "Claude feature added: mid-conversation system message", as of 2026-09-22. Claim clm_E25E4DA5DE4D, https://asof.is/claim/clm_E25E4DA5DE4D, accessed 2026-11-08. Source: https://platform.claude.com/docs/en/release-notes/overview#2026-09-22.  
checked: 2026-11-07 · its source page states the value and the date  

> Tools can now be defined inside a mid-conversation system message , in beta on the Claude API with the inline-tools-2026-09-15 beta header.

What https://platform.claude.com/docs/en/release-notes/overview#2026-09-22 says, word for word.

## Sources

- https://platform.claude.com/docs/en/release-notes/overview#2026-09-22 (primary, Anthropic, published 2026-09-22)

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