You asked about Monitoring
18 people built something like it. 2 are gone.
That is 12% of the ones whose fate we could settle, against 23% across the whole register. 1 were acquired.
| Launched | What it was | Today |
|---|---|---|
| 2022-03-15 | zipy.ai | still up |
| 2024-01-01 | YCRespan Self-driving observability, evals, and gateway for AI agents · respan.ai | still up |
| 2023-08-09 | hawkflow.ai | unverified |
| 2019-06-01 | YCTraces Transform your video monitoring with AI · traces.ai | still up |
| 2024-06-01 | YCCoval Simulation & Evaluation that scales voice and chat AI agents · coval.dev | still up |
| 2024-01-01 | YCRaindrop Sentry for AI Agents · raindrop.ai | still up |
| 2025-01-01 | AI performance monitoring for factory workers · optifye.ai | still up |
| 2023-05-17 | printnanny.ai | gone |
| 2018-01-01 | iPhone-based driver monitoring for commercial fleets. · observantai.com | still up |
| 2025-06-01 | Implantable microchips and AI for cattle monitoring · nexa.farm | acquired |
| 2018-06-01 | Distributed AI for Industrial Process Monitoring and Optimization. · numericcal.com | gone |
| 2021-06-01 | Open-source monitoring for machine learning models · evidentlyai.com | still up |
| 2026-06-01 | AI that runs factories. · controlseat.com | still up |
| 2025-09-01 | YCLemma Production Monitoring for AI agents · uselemma.ai | still up |
| 2025-09-01 | Find what's losing you customers and money in your AI agent and fix it · thecontextcompany.com | still up |
| 2024-01-01 | YCClarum AI agents for private market diligence, monitoring, and reporting · clarum.ai | still up |
| 2023-06-01 | YCParea Test, evaluate & observe your LLM applications · parea.ai | still up |
| 2021-01-01 | YCParsagon AI to track and analyze public policy · parsagon.io | still up |
| 2026-06-01 | We find where AI agents fail, then train better models to run them. · agnost.ai | still up |
How this compares
Y Combinator reports its own outcomes, including acquisitions. The other two are judged by asking the domain, so they are not measured the same way and are never averaged together.
The register re-probes every domain it holds. Some that answered last month stop answering. We send that list — what went quiet, and what it was — once a month. Nothing else.
How this was made. Show HN entries are every post from 2021 to 2023 with at least five points that linked to its own domain; code hosts and free hosting are excluded, because a repository outlives the effort behind it. Product Hunt entries needed 100 votes — a far higher bar, so they are the promoted top slice rather than a like-for-like sample. Both are judged by asking the domain whether it still answers: gone means it no longer resolves, refuses the connection, serves a parking page, or says plainly that it shut down. An HTTP error is not counted as gone — a server answering 404 is one somebody still pays for, and an audit of 25 gone-calls found two such sites alive with only a moved homepage. Y Combinator entries use the status YC publishes itself, which is why only those can say acquired. Squatted domains — a lapsed name now serving somebody else's site — are not detected, so these figures run slightly low.