Jsonschema MCP Server

by mrfentmen Your server? Claim it

local only

Jsonschema MCP runs on your own machine — the client starts it, so there is no endpoint to ping. 544 installs a week from npm. Last commit 28 Oct 2026.

Validate JSON against a JSON Schema offline, with a clear list of every structural error

Installs per day peak 509 · avg 18

a month agotoday

544

Installs / week

npm · @mrfentmen/jsonschema-mcp

Stars

0 open issues

28 Oct 2026

Last commit

from GitHub

—

License

TypeScript

Nothing serious here today

Today is the operative word: we check Jsonschema MCP every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.

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.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add jsonschema-mcp -- npx -y @mrfentmen/jsonschema-mcp

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "jsonschema-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@mrfentmen/jsonschema-mcp"
      ]
    }
  }
}

~/.codex/config.toml

[mcp_servers.jsonschema-mcp]
command = "npx"
args = ["-y", "@mrfentmen/jsonschema-mcp"]

.cursor/mcp.json

{
  "mcpServers": {
    "jsonschema-mcp": {
      "command": "npx",
      "args": [
        "-y",
        "@mrfentmen/jsonschema-mcp"
      ]
    }
  }
}

.vscode/mcp.json

{
  "servers": {
    "jsonschema-mcp": {
      "type": "stdio",
      "command": "npx",
      "args": [
        "-y",
        "@mrfentmen/jsonschema-mcp"
      ]
    }
  }
}

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Jsonschema MCP — questions

Answers built from our own checks of this server.

Why is there no uptime for Jsonschema MCP?

Jsonschema MCP 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 @mrfentmen/jsonschema-mcp was installed 544 times last week.

How do I connect Jsonschema MCP?

Copy the ready config from this page. We generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each in the form that client actually reads. It runs locally, so the command pulls @mrfentmen/jsonschema-mcp straight from npm; nothing to host, nothing to sign up for.

How many people use Jsonschema MCP?

The npm package @mrfentmen/jsonschema-mcp was installed 544 times in the last week. We show installs rather than GitHub stars on purpose: a star is a bookmark, an install is someone actually running it.

Is Jsonschema MCP open source?

We cannot say either way: written in TypeScript and 0 stars on GitHub, but we could not determine the licence, and without one the code is not open source by default.