Mockd, developed by Getmockd, is an MCP server and a high-performance, multi-protocol mock server built using Go. It supports diverse protocols like HTTP, WebSocket, gRPC, and GraphQL. Mockd provides developers, testers, and AI agents with a powerful environment for API prototyping, automated testing, and AI agent development. Its capabilities extend to creating digital twins and managing mock APIs programmatically, making it a valuable asset for controlled system interaction.

What does Mockd connect to?

Mockd serves as a Model Context Protocol (MCP) server, connecting directly to AI agents and clients. It functions primarily as a high-performance, multi-protocol mock server, supporting HTTP, WebSocket, gRPC, MQTT, SSE, GraphQL, and SOAP. This enables it to simulate various network interactions. Compatible AI clients include Claude Desktop, Cursor, Windsurf, any MCP-compatible editor, Claude Code, Cline, and OpenCode, allowing for broad integration with AI development workflows.

Core features and tools

Mockd exposes a built-in Model Context Protocol server equipped with 18 distinct tools. These tools address various aspects of mock server management and interaction. Key categories covered include mock CRUD, stateful resources, chaos injection, request logs, verification, workspaces, and import/export. These functionalities empower users to precisely control mock behaviors, manage testing environments, and monitor system interactions.

Who is it for?

Mockd targets developers, testers, and AI agents/developers seeking to manage and test API interactions. It assists in rapid API prototyping, automated testing in CI/CD, and AI agent development by providing controlled environments. Its multi-protocol support and MCP server capabilities make it suitable for complex development and testing scenarios across different technologies. This is not the right fit if your workflow strictly requires explicit documentation of all MCP server transport protocols.

How to get started

When using the CLI to add mocks, authentication for the admin API is handled automatically. The "mockd start" command can be run with a "--no-auth" flag.

Use cases

• Rapid API Prototyping and Development: Developers quickly create and iterate mock APIs for multiple protocols (HTTP, gRPC, GraphQL) via CLI or configuration, without backend dependencies.
• Automated Testing in CI/CD Pipelines: Mockd integrates into CI/CD pipelines, giving fast, deterministic mock responses for integration tests, lessening external service reliance.
• AI Agent Development and Testing: AI agents utilize the MCP server to programmatically manage and verify mock APIs, build digital twins, and test interactions in controlled settings.

Mockd offers a powerful solution for simulating multi-protocol APIs and interacting with AI agents via its MCP server. Its support for diverse protocols and integration into development and testing workflows makes it a versatile tool. The array of built-in tools for mock management, stateful resources, and chaos injection provides fine-grained control over testing environments. Try creating a mock API for an HTTP endpoint and testing it with a compatible AI client.