Deed — Claude Code MCP server: what it does, how to install
A contract-first language environment and toolchain designed for reviewing agent-generated code. It checks effects, types, and patch receipts over MCP.
Open on GitHubWhat Deed does
Deed connects coding agents to a contract-oriented language. Its toolchain analyzes system capabilities alongside effect rows. Validation happens through explicit contracts. The system also inspects receipts before and after patch application, helping human reviewers inspect machine-generated logic.
Using the server requires an existing Rust setup. The deed-lang package installs the deed executable on your machine. Running deed mcp exposes the stdio interface for client integration.
What it helps with
- validate contract compliance and types in machine-written code
- inspect capability boundaries and effect rows
- verify patch receipts before and after modifications
- run test suites and project checks through an agent
Example prompts for the agent
- Run deed check greeting to verify all contracts and capabilities
- Create a new project using deed new and run test suites with deed test
- Examine the latest patch receipt using the deed mcp connection
How to install Deed
Install
The MCP registry has no launch command for it: see the repository README
Step by step, with commands for each platform: How to add an MCP server to Claude Code, Codex, Cursor, VS Code, Gemini CLI and more
Questions about Deed
How to install Deed in Claude Code?
Install the binary by running cargo install deed-lang. After that, configure Claude Code to launch deed mcp over stdio or use the registry identifier io.github.deed-lang/deed.
What does Deed do?
Deed provides tooling for a contract-first programming language. It checks patch receipts, effects, and system permissions to make machine-written code straightforward for humans to audit.
How does Deed communicate with development tools?
Deed runs a local Model Context Protocol server over standard I/O. Start it anytime with deed mcp.
