Generating .NET SDKs from OpenAPI Specs with AutoSDK

Overview

AutoSDK is a .NET CLI tool and Roslyn source generator that produces production-quality C# SDKs from OpenAPI specifications. Generated SDKs include:

• Fully typed C# clients with async methods and CancellationToken support
• System.Text.Json serialization (no reflection, NativeAOT/trimming compatible)
• Nullable reference types enabled
• Support for OneOf/AnyOf/AllOf schemas
• Server-Sent Events (SSE) streaming via application/x-ndjson
• Enum serialization for System.Text.Json
• Polyfills for .NET Framework / .NET Standard targets
• Strong-named assemblies

AutoSDK is used in 30+ real SDKs (OpenAI, Anthropic, Ollama, HuggingFace, etc.) and tested against OpenAPI specs up to 220k lines.

Quick Start Workflow