# 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`](./src/index.ts) or the official protocol docs at . --- ## 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 ```jsonc { "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 ```jsonc { "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) ```jsonc { "mcpServers": { "celp-mongo": { "command": "npx", "args": ["-y", "celp-mcp"], "env": { "DATABASE_TYPE": "mongodb", "MONGO_URL": "mongodb://analytics_user:pw@db1.example.com:27017/marketing?authSource=admin&ssl=true", "CELP_API_KEY": "sk-..." } } } } ``` ### 5.4 Databricks SQL Warehouse ```jsonc { "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 ```bash 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`](./src/index.ts). Tool definitions live in [`src/initTools.ts`](./src/initTools.ts). --- ## 9 • License Released under the **MIT License** – see [`LICENSE`](./LICENSE) for full text.