Nullprint MCP server

nullprint-mcp

An MCP server for Nullprint, the multi-profile browser. It lets any MCP-capable AI agent (Claude Code, Claude Desktop, OpenAI Codex, Kimi, …) create browser profiles, launch them, run consistency check-ups and drive the pages inside a running profile.

<!-- mcp-name: io.github.nullprintai/nullprint-mcp -->

The server is a thin layer over the local Nullprint daemon's HTTP API: every tool maps to one daemon endpoint. The daemon, the browser kernels and the fingerprint engine ship with the Nullprint desktop app and are not part of this package.

Requirements

• Nullprint desktop app installed and running (Windows or macOS), signed in. Download: https://nullprint.ai
• Python 3.11+ on the same machine. The easiest way to run the server is uv, which installs the package on first use.

Install

# Claude Code
claude mcp add nullprint -- uvx nullprint-mcp

# OpenAI Codex
codex mcp add nullprint -- uvx nullprint-mcp

Claude Desktop, Kimi and other clients that use an mcpServers config file:

{
  "mcpServers": {
    "nullprint": {
      "command": "uvx",
      "args": ["nullprint-mcp"]
    }
  }
}

Without uv: pip install nullprint-mcp, then use nullprint-mcp as the command (no args).

No port or key to configure: the server reads the running daemon's port and API key from ~/.nullprint/daemon.json, which the desktop app writes on start-up. To point at a daemon elsewhere, pass --daemon-url http://host:port (or --port 7801 for localhost) and set NULLPRINTAPIKEY. Resolution order, most explicit first:

1. --daemon-url / --port
2. NULLPRINTDAEMONURL
3. NULLPRINT_PORT
4. ~/.nullprint/daemon.json (NULLPRINT_HOME changes the directory)

If the daemon is not running the tools say so plainly instead of throwing a connection trace.

Tools

Notes that matter when writing prompts:

Shortened. The full README is on GitHub.