graphjin-mcp

GraphJin - A Compiler to Connect AI to Your Databases

Point GraphJin at any database and AI assistants can query it instantly. Auto-discovers your schema, understands relationships, compiles to optimized SQL. No configuration required.

Works with PostgreSQL, MySQL, MongoDB, SQLite, Oracle, MSSQL, Snowflake - and models from Claude/GPT-4 to local 7B models.

Installation

npm (all platforms)

npm install -g graphjin

macOS (Homebrew)

brew install dosco/graphjin/graphjin

Windows (Scoop)

scoop bucket add graphjin https://github.com/dosco/graphjin-scoop
scoop install graphjin

Linux

Download .deb/.rpm from releases

Docker

docker pull dosco/graphjin

Try It Now

This is a quick way to try out GraphJin we'll use the --demo command which automatically starts a database using docker and loads it with demo data.

Download the source which contains the webshop demo

git clone https://github.com/dosco/graphjin
cd graphjin

Now launch the Graphjin service that you installed using the install options above

graphjin serve --demo --path examples/webshop

You'll see output like this:

GraphJin started
───────────────────────
  Web UI:      http://localhost:8080/
  GraphQL:     http://localhost:8080/api/v1/graphql
  REST API:    http://localhost:8080/api/v1/rest/
  Workflows:   http://localhost:8080/api/v1/workflows/<name>
  MCP:         http://localhost:8080/api/v1/mcp

Claude Desktop Configuration
────────────────────────────
Add to claude_desktop_config.json:

  {
    "mcpServers": {
      "Webshop Development": {
        "command": "/path/to/graphjin",
        "args": ["mcp", "--server", "http://localhost:8080"]
      }
    }
  }

Copy the JSON config shown and add it to your Claude Desktop config file (see below for file location). You can also click File > Settings > Developer to get to it in Claude Desktop. You will also need to Restart Claude Desktop

OS	Possible config file locations
macOS	~/Library/Application Support/Claude/claude_desktop_config.json
Windows	%APPDATA%\Claude\claude_desktop_config.json

MCP install for OpenAI Codex + Claude Code

GraphJin includes a guided installer that configures MCP for OpenAI Codex, Claude Code, or both.

# Guided mode (asks target client and scope)
graphjin mcp install

OpenAI Codex

graphjin mcp install --client codex --scope global --yes

Claude Code

graphjin mcp install --client claude --scope global --yes

Troubleshooting

• graphjin mcp install defaults to --server http://localhost:8080/.
• Set a custom server URL with --server, for example:
  • graphjin mcp install --client codex --server http://my-host:8080/ --yes
• Claude installs use graphjin mcp --server <url> under the hood.
• If Codex CLI does not support codex mcp add --scope (older versions), GraphJin automatically falls back to updating:
  • global scope: ~/.codex/config.toml
  • local scope: .codex/config.toml

Getting started

To use GraphJin with your own databases you have to first create a new GraphJin app, then configure it using its config files and then launch GraphJin.

Step 1: Create New GraphJin App

graphjin new my-app

Step 2: Start the GraphJin Service

graphjin serve --path ./my-app

Step 3: Add to Claude Desktop config file

Copy paste the Claude Desktop Config provided by graphjin serve into the Claude Desktop MCP config file. How to do this has been defined clearly above in the Try it Now section.

Step 4: Restart Claude Desktop