Anthropic acquires Stainless, doubling down on agent connectivity
Anthropic has acquired Stainless, a company specializing in API SDK generation and MCP (Model Context Protocol) server tooling.
Founded in 2022, Stainless has powered every official Anthropic SDK since the API’s earliest days, supporting TypeScript, Python, Go, Java, Kotlin, and more. Hundreds of companies rely on Stainless to generate SDKs, CLIs, and MCP servers — the libraries and connectors that let both developers and agents consume APIs.
Katelyn Lesse, Head of Platform Engineering at Anthropic, put it plainly: “Agents are only as useful as what they can connect to. We’re excited to bring the Stainless team into Anthropic to advance Claude’s ability to connect to data and tools.”
The acquisition signals a clear strategic shift: Anthropic is moving from being a “model company” to an “agent platform company.” MCP is the bridge for Claude to reach into external systems, and Stainless has been the core builder of that bridge. Bringing SDK and MCP tooling in-house means Anthropic can ship new API integrations faster and lower the barrier for third-party developers to connect their tools to Claude.
With Google pushing A2A (Agent-to-Agent) and OpenAI also investing in tool use, who controls the “connectivity layer” of AI agents will determine who owns the infrastructure of the agent economy.