mcpbeat

JSON Contracts MCP Server

io.github.json-contracts/json-contracts
local only

JSON Contracts runs on your own machine — the client starts it, so there is no endpoint to ping. 44 installs a week from npm. Last commit 5 May 2026.

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

Installs per day peak 28 · avg 9 · -28% w/w
a month agotoday
44
Installs / week
npm · json-contracts
1
Stars
0 open issues
5 May 2026
Last commit
0 releases in 90 days
NOASSERTION
License
TypeScript

Connect this server

This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.

run in your terminal
claude mcp add json-contracts -- npx -y json-contracts
~/Library/Application Support/Claude/claude_desktop_config.json
{
  "mcpServers": {
    "json-contracts": {
      "args": [
        "-y",
        "json-contracts"
      ],
      "command": "npx"
    }
  }
}
~/.codex/config.toml
[mcp_servers.json-contracts]
command = "npx"
args = ["-y", "json-contracts"]
.cursor/mcp.json
{
  "mcpServers": {
    "json-contracts": {
      "args": [
        "-y",
        "json-contracts"
      ],
      "command": "npx"
    }
  }
}
.vscode/mcp.json
{
  "mcpServers": {
    "json-contracts": {
      "args": [
        "-y",
        "json-contracts"
      ],
      "command": "npx"
    }
  }
}

JSON Contracts — questions

Answers built from our own checks of this server.

Why is there no uptime for JSON Contracts?
JSON Contracts runs on your own machine over stdio — there is no network address to reach, so uptime cannot be measured for it by anyone. What can be measured is adoption: the npm package json-contracts was installed 44 times last week.
How do I connect JSON Contracts?
Copy the ready config from this page — we generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each with the file path that client actually reads. It runs locally, so the command pulls json-contracts straight from npm; nothing to host, nothing to sign up for.
How many people use JSON Contracts?
The npm package json-contracts was installed 44 times in the last week. Week over week that is -28%. We show installs rather than GitHub stars on purpose: a star is a bookmark, an install is someone actually running it.
Is JSON Contracts open source?
Yes — it is published under the NOASSERTION licence, written in TypeScript and 1 stars on GitHub. The source link is on this page, so you can read exactly what it does with your data before you connect it.