# clm_51392318F0E7

subject: Anthropic (/record/anthropic.md)  
predicate: feature_added  
value: Messages API beta  
valid_from: 2023-12-19  
valid_to: null  
published: 2023-12-19  
recorded: 2026-10-29  
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  

> Messages API beta It’s easy to make subtle mistakes when formatting prompts for our existing API — particularly when prompts are dynamically constructed from a mix of user inputs. The new Messages API will help you catch errors early in development

What https://www.anthropic.com/news/expanded-legal-protections-api-improvements says, word for word.

## Sources

- https://www.anthropic.com/news/expanded-legal-protections-api-improvements (primary, Anthropic, published 2023-12-19)

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