Summary & Key Takeaways ​

• Simon Willison leveraged Claude Fable to review sqlite-utils 4.0rc1 for release blockers.
• Claude Fable identified a critical data loss bug in Table.delete_where() that prevented commits.
• The AI agent's review process involved 37 prompts, 34 commits, and extensive code changes.
• The total cost for Claude Fable's assistance in this project was approximately $149.25.
• The collaboration led to several design improvements beyond just bug fixes.
• This intervention prevented a major bug from shipping in a stable release.

Our Commentary ​

This is genuinely fascinating. I'm always a bit skeptical about AI coding agents, but preventing a data loss bug in a major release? That's a huge win. The cost is also surprisingly low for such a critical intervention. It makes me wonder how many other projects could benefit from this kind of AI-assisted QA. We're seeing AI move beyond just generating code to actively improving its quality in ways humans might miss.