Celp-MCP – Database & Analytics Server for the Model-Context-Protocol

TL;DR for LLMs
Connect via MCP stdio transport, call initialize, then use one of the four tools described below.
Tools are idempotent and expect structured JSON arguments – never place credentials inside the prompt field.

1 • What this server does

celp-mcp exposes natural-language analytics over SQL, MongoDB and Databricks warehouses to any MCP-compatible client.
Internally it hosts a light agent that

1. maps NL questions → multi-step SQL / Mongo / Spark plans,
2. executes those plans locally against the database (no data leaves the machine), and
3. streams back markdown reports with tables, charts and findings.

The server follows the Model-Context-Protocol (MCP) 2025-03-26 spec and ships with the standard stdio transport.
No network sockets are opened unless you start the optional remote streaming helper.

2 • Exposed MCP tools

| Name | Purpose | Speed vs Reasoning | Required params | |------|---------|--------------------|-----------------| | query-database | High-fidelity multi-step analysis | ⭐ Accuracy | prompt (string), optional databaseConfig, databaseConnectionId, celpApiKey | | query-database-turbo | One-shot, single-query path | ⚡ Speed | same as above | | get-schema | Return schema map the agent would use | – | same as above (all optional) | | get-index-map | Return index / key map for optimisation | – | same as above (all optional) |

2.1 Tool argument schemas (abridged)

3 • Plug-and-play usage

For most users no manual JSON-RPC calls are necessary. Any modern MCP client (Claude Desktop, Cursor, @modelcontextprotocol/sdk, etc.) will:

1. Spawn the server as a subprocess via the command provided in your config (see Section 5).
2. Negotiate the MCP handshake automatically.
3. Surface the four tools (query-database, query-database-turbo, get-schema, get-index-map) to the language model.

All you have to supply are

• the command & args (usually npx -y celp-mcp), and
• the environment variables for your database + CELP_API_KEY.

If you are building a custom MCP client and need low-level details (e.g. raw initialize / call_tool payloads), see the annotated code in src/index.ts or the official protocol docs at https://modelcontextprotocol.io.

4 • Essential environment variables

At minimum the process needs:

| Database | Required vars | |----------|---------------| | Postgres/MySQL | DATABASE_TYPE · DATABASE_HOST · DATABASE_USER · DATABASE_PASSWORD · DATABASE_NAME | | MongoDB | Either the five above or a single MONGO_URL | | Databricks | DATABASE_TYPE=databricks · DATABRICKS_HOST · DATABRICKS_TOKEN · DATABRICKS_HTTP_PATH · DATABRICKS_CATALOG |

And for every setup:

• CELP_API_KEY – authorises the orchestration backend.

That's all an MCP client must supply.
See docs/ADVANCED.md if you want SSL flags, replica-set tuning, debug logging, etc.

5 • Claude / Cursor integration recipes

Place the JSON block below in:

• Claude Desktop → ~/Library/Application Support/Claude/claude_desktop_config.json
• Cursor (VS Code) → your Settings JSON or .vscode/mcp.json

5.1 PostgreSQL

{
  "mcpServers": {
    "celp-postgres": {
      "command": "npx",
      "args": ["-y", "celp-mcp"],
      "env": {
        "DATABASE_TYPE": "postgres",
        "DATABASE_HOST": "127.0.0.1",
        "DATABASE_PORT": "5432",
        "DATABASE_USER": "readonly",
        "DATABASE_PASSWORD": "supersecret",
        "DATABASE_NAME": "analytics",
        "PG_DISABLE_SSL": "true",
        "CELP_API_KEY": "sk-..."
      }
    }
  }
}

5.2 MySQL

{
  "mcpServers": {
    "celp-mysql": {
      "command": "npx",
      "args": ["-y", "celp-mcp"],
      "env": {
        "DATABASE_TYPE": "mysql",
        "DATABASE_HOST": "db.internal",
        "DATABASE_PORT": "3306",
        "DATABASE_USER": "readonly",
        "DATABASE_PASSWORD": "pw",
        "DATABASE_NAME": "ecommerce",
        "CELP_API_KEY": "sk-..."
      }
    }
  }
}

5.3 MongoDB (connection-string form)

{
  "mcpServers": {
    "celp-mongo": {
      "command": "npx",
      "args": ["-y", "celp-mcp"],
      "env": {
        "DATABASE_TYPE": "mongodb",
        "MONGO_URL": "mongodb://analytics_user:[email protected]:27017/marketing?authSource=admin&ssl=true",
        "CELP_API_KEY": "sk-..."
      }
    }
  }
}

5.4 Databricks SQL Warehouse

{
  "mcpServers": {
    "celp-dbx": {
      "command": "npx",
      "args": ["-y", "celp-mcp"],
      "env": {
        "DATABASE_TYPE": "databricks",
        "DATABRICKS_HOST": "adb-1234567890.2.azuredatabricks.net",
        "DATABRICKS_TOKEN": "dapiXXXXXXXXXXXXXXXX",
        "DATABRICKS_HTTP_PATH": "/sql/1.0/warehouses/0123456789abcdef",
        "DATABRICKS_CATALOG": "main",
        "CELP_API_KEY": "sk-..."
      }
    }
  }
}

After saving, restart Claude / Cursor. The server will be launched on demand and the four tools will be advertised to the language model automatically.

6 • Advanced usage & orchestration API

query-database* tools ultimately send work to an LLM-driven orchestration service at https://celp-celp-mcp.onrender.com.
To override (e.g., when self-hosting) set STREAMING_API_URL.

The path src/index.ts::orchestrate shows the full client–socket workflow, including schema pre-upload and incremental chunk handling. Feel free to reuse it for custom front-ends.

7 • Security & privacy

• All SQL / Mongo / Spark queries run locally.
• The orchestration service only receives generated SQL, never raw data.
• Credentials are kept in the process env, never serialized over MCP or sockets.

For production deployments we recommend:

1. Provision a read-only DB user.
2. Restrict network access to the DB port.
3. Rotate CELP_API_KEY regularly.
4. Audit agent prompts to avoid prompt-injection.

8 • Development

git clone https://github.com/CelpAI/celp-mcp.git
cd celp-mcp
pnpm install
pnpm build && pnpm start              # runs built JS
pnpm dev                               # ts-node + watch

The main entry point is src/index.ts.
Tool definitions live in src/initTools.ts.

9 • License

Released under the MIT License – see LICENSE for full text.