MCP Contract Diff Tool

Example Use Cases

• 1

  Detect breaking changes in MCP tool schemas before deployment.

• 2

  Audit and review tool description changes to prevent tool poisoning attacks.

• 3

  Pin and verify MCP tool contracts to avoid schema drift.

Description

mcp-contracts provides a CLI tool called mcpdiff that captures snapshots of MCP server tool schemas, allowing users to version, diff, and validate these schemas. It helps detect breaking changes, description modifications that could indicate tool poisoning, and schema drift, ensuring agents can trust the tool contracts they rely on. The tool integrates easily with CI systems and supports multiple commands for snapshotting, diffing, baseline management, and inspection.