Anthropic has acquired Stainless, the developer-tools company that generates official SDKs for OpenAI, Google, Anthropic, Cloudflare and other AI platforms.
The price was not disclosed, but reports put it above $300 million, roughly twice Stainless’s late-2024 valuation.
Stainless turns API specifications into TypeScript, Python, Go, Java and Kotlin SDKs, then keeps them synchronized as APIs change. That makes it plumbing for developers, not a front-end feature.
The strategic point is agents. If Claude is meant to operate real software, Anthropic wants tighter control over the connectors, SDKs and MCP servers that let models reach outside systems.
Sources: CocoLoop, Anthropic acquires Stainless (Anthropic Blog), Anthropic has acquired the dev tools startup used by OpenAI, Google, and Cloudflare (TechCrunch), Anthropic Acquires Stainless for Over $300M (Analytics Insight)