The frontier of AI is moving from models that respond to agents that take action-and agents are only as capable as the systems they can access. Anthropic has acquired Stainless, a company specializing in SDKs and MCP server tooling, to extend that reach further.
Founded in 2022, Stainless has powered the generation of every official Anthropic SDK since the earliest days of Anthropic's API. Hundreds of companies depend on Stainless to generate SDKs, CLIs, and MCP servers-the libraries, command-line tools, and connectors that enable developers and agents to interact with an API. Stainless converts an API spec into SDKs across TypeScript, Python, Go, Java, Kotlin, and other languages. Each SDK is fast, reliable, and designed to feel native in its respective language.
Katelyn Lesse, Head of Platform Engineering at Anthropic, noted that Stainless has shaped how developers experience the Claude API from the beginning and that it has been a productive collaboration. She emphasized that agents are only as useful as the things they can connect to, and expressed enthusiasm about bringing the Stainless team into Anthropic to advance Claude's ability to connect to data and tools.
Alex Rattray, Founder and CEO of Stainless, shared that he started the company because SDKs deserve as much attention as the APIs they wrap, and that Anthropic was one of the first teams to embrace that vision. He said the team had been watching what developers built on Claude over the past few years, which made joining forces a straightforward decision. The Stainless team will continue doing the work they are passionate about, now on the platform where it has the greatest impact.
Anthropic created MCP to make agent connectivity possible. By uniting the Stainless and Anthropic teams, the Claude Platform continues to advance the frontier of developer experience and agent connectivity.