Observed arrival · 2026-10-10
Breakspec finds the bug the agent’s tests missed
Breakspec is a proposed testing tool for AI-written code: it checks approved rules against inputs the code’s own tests may have missed.
○Open
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$Paid
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✦Pretty
●Pro
◎Niche
◉Human
⚑Risk
ƒJS
- For
- Developers testing code written by AI agents
- Worth noticing
- The example uses the rule “the shares add up to the bill” to expose a failure at total_cents: 1 and people: 2.
Field notes
The sample rule is that the returned shares must add up to the original bill, a condition the agent's hand-picked examples fail to challenge. The page says users approve suggested rules and input ranges before testing begins, and describes running checks again on pull requests. Its interactive example runs a JavaScript copy in the browser; the site describes the real-code version as running in an isolated sandbox.
Observed signals
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Editorial observations of this landing page, not a rating.
○OpenPublic substance visible
✦PrettyNotable craft visible
◎NicheUnusually specific use
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