# Claude Fable 5.2 merges repeated code more often when told it owns the codebase

> Original title: Quoting Prompting Claude Fable 5.2

- Source: Simon Willison
- Published: 2026-11-10T05:34:14.000Z
- Bad Influence: https://badinfluence.news/items/w1vvf31zxddby9nc1qzigvrbr
- Original: https://simonwillison.net/2026/Nov/10/prompting-claude-fable-52/

## Summary

Anthropic says Claude Fable 5.2 merged repeated code in about half of its tries on small coding tasks when the prompt said the codebase was its own, and in under a tenth of tries without that wording. The model tended to add to existing structure when the prompt was silent on ownership or presented the code as someone else's.