mockd

Mockd supports seven protocols—HTTP, WebSocket, gRPC, MQTT, SSE, GraphQL, and SOAP—from a single binary, eliminating the need for multiple specialized tools, as shown in the feature comparison table.

It can import OpenAPI specs and bind them to stateful tables, creating mocks that pass real SDK tests, such as 49/49 Stripe Go SDK tests, ensuring high fidelity for services like Stripe and Twilio.

Built-in Model Context Protocol server with 18 tools allows AI agents to create and manage mocks directly, integrating with editors like Claude Desktop and Cursor, as described in the MCP section.

Supports importing from OpenAPI, Postman, HAR, WireMock, cURL, and WSDL formats, and exporting mocks, facilitating easy migration and sharing across different tools.

Features like latency injection, error rates, and circuit breakers enable resilience testing without additional tools, with commands like `mockd chaos apply flaky` for automated chaos scenarios.