Stainless
Generate best-in-class SDKs, docs, and MCP servers from your OpenAPI spec
Founded
N/A
Starting Price
Free
Category
Developer Tools
Last updated March 14, 2026
About Stainless
Stainless generates production-quality SDKs, documentation, and MCP servers from your OpenAPI spec. It supports TypeScript, Python, Go, Java, Kotlin, Ruby, PHP, and C#, with plans for Rust and Swift. Used by OpenAI, Anthropic, Meta, Cloudflare, and Runway, Stainless handles SDK publishing to package registries, versioning, and changelog generation. Its docs platform combines API reference, usage examples, and narrative guides in one cohesive experience, while MCP servers enable coding models to reliably generate code for your API.
Pros & Cons
Pros
- Trusted by industry leaders (OpenAI, Anthropic, Meta, Cloudflare) — proven at massive API scale
- Generated SDKs are genuinely idiomatic and production-quality, not just auto-generated boilerplate
- Automated publishing and versioning eliminates the manual toil of maintaining SDKs across 8+ languages
- MCP server generation is unique — enables AI coding assistants to use your API effectively
- Free tier with 5 SDKs and 25 endpoints is generous enough for startups and small APIs
Key Features
Multi-Language SDK Generation
Generate idiomatic SDKs in TypeScript, Python, Go, Java, Kotlin, Ruby, PHP, and C# from a single OpenAPI spec
Automated Publishing
Push SDK updates to npm, PyPI, Maven, and other package registries automatically as your API evolves
Docs Platform
Unified API reference, usage examples, and narrative guides that auto-update with API changes
MCP Server Generation
Generate MCP servers that enable AI coding assistants to reliably use your API
Versioning & Changelogs
Automatic semantic versioning and changelog generation for every SDK update
API Spec Validation
Catch OpenAPI spec issues before they become SDK bugs with built-in validation
Custom SDK Configuration
Control naming conventions, error handling, pagination, and retries per language target
Pricing
Free
Free
- Up to 5 SDKs
- 25 endpoints
- Community support
- Basic docs
- Public repos
Best For
API-First Companies
Generate and maintain SDKs across all major languages as your API evolves, without a dedicated SDK team
Developer Experience
Provide developers with idiomatic, well-documented SDKs that make your API easy to integrate
AI Integration
Generate MCP servers so AI coding assistants can reliably write code that uses your API
Open Source Projects
Maintain open-source SDKs with automated publishing and changelogs from a free plan
