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Find out how your AI agent fails. Before your users do.
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Almost every team now runs AI in production, but few know how it behaves once real users show up. The failures are quiet: a wrong refund policy, a made-up order status. Nothing crashes, so you hear about it from your users. three.dev finds those failures in your live traffic on its own and ranks them by severity. Setup is one prompt to Claude Code, Cursor, or Codex. Then your coding agent gets what it needs to write the fix.
PH · launched Nov 12, 2026 · 131 upvotes (top 1%) · 0 views
Niche: ai agent evaluation platforms · 182 launches, 8 in the last 7 days ▼ -50% · Explore this niche →
Category and tags
- Horizontal
- Observability & eval
- Developer
- AI-native
- Commercial product
- Analytics
- Developer Tools
- Artificial Intelligence
Visit website ↗ Source listing ↗
More like this: all 182 launches in ai agent evaluation platforms →
Could you build this?
Partial The dashboard, SDK, and trace ingestion are vibe-codeable, but reliably detecting subtle failures like wrong policy answers in live traffic depends on evaluation methodology and labeled data that are hard to build.
What it would actually take: The stack would be a lightweight tracing SDK or proxy that captures LLM inputs and outputs, a pipeline that runs LLM-as-judge or rule-based evaluators over sampled traffic, clustering to rank failure modes, and an alerting UI. The hard parts are evaluator accuracy (low false positives) and grounding checks against each customer's policies and data, which requires evaluation research and a lot of domain-specific calibration.
Competitors
Other products that read as similar to this one : 1149 launches clear the similarity bar, closest 8 shown.
Attention rank: #19 of 1150 (itself plus its competitors, highest first, normalized so YC and Product Hunt are compared fairly).
Launched 373 days after the earliest competitor.
- Midwater · ph · 2026-10-19 · 2 upvotes · similarity 0.61
- Agent Reliability Toolkit · ph · 2026-09-10 · 1 upvotes · similarity 0.56
- Fabraix · ph · 2026-05-08 · 196 upvotes · similarity 0.56
- Agent Checker · ph · 2026-09-06 · 2 upvotes · similarity 0.54
- Continue · hn · 2026-02-17 · 44 upvotes · similarity 0.53
- ClientCoded · ph · 2026-10-22 · 1 upvotes · similarity 0.53
- AI Agent Observability · ph · 2026-10-01 · 2 upvotes · similarity 0.53
- AgentX · ph · 2026-06-22 · 523 upvotes · similarity 0.52
The niche, labels, vibe code rating and competitor comparison on this page are analysis by Nicheloom. If you use them, please credit nicheloom.com. How you may use our data.