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mcp/harbor
Claude Desktop

JSON Contracts for Claude Desktop

io.github.json-contracts/json-contracts

JSON contract registry and validator for structured LLM and agent outputs.

client:Claude Desktop transport:stdio runtime:npm

Install JSON Contracts in Claude Desktop

~/Library/Application Support/Claude/claude_desktop_config.json · windows: %APPDATA%\Claude\claude_desktop_config.json

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{
  "mcpServers": {
    "json-contracts": {
      "command": "npx",
      "args": [
        "-y",
        "json-contracts"
      ],
      "env": {
        "JSON_CONTRACTS_DIR": "<JSON_CONTRACTS_DIR>"
      }
    }
  }
}

Settings → Developer → Edit Config opens this file. Restart the app after saving. Claude Desktop docs

JSON Contracts in other clients

JSON Contracts MCP server