Stainless generates idiomatic, production-ready client SDKs from OpenAPI specifications with features like automatic pagination, retries, streaming, and proper error handling baked in. Used by Anthropic, OpenAI, Cloudflare, and Lithic to maintain their official SDKs. Produces TypeScript, Python, Go, Java, and Kotlin SDKs that match hand-written quality with automated maintenance and versioning.
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Speakeasy uses AI to parse backend API routes and auto-generate production-ready SDKs in multiple languages alongside OpenAPI documentation. It ensures that client libraries and documentation always match the current backend implementation, eliminating the drift between API code, SDK behavior, and documentation that plagues most API-first teams as their services evolve.
Paid; pricing based on SDK languages and API volume