mcp-registry/legion-mcp

    ==================
      
       /// MCP ///
      /// LEG ///
        
    ==================
        
    [server:online]
    [protocol:ready]

legion-mcp

by TheRaLabs

A Python MCP server that exposes multi-database querying capabilities through Legion Query Runner and the Model Context Protocol.

56
12
Open Source
GitHubWebsite

01

execute_query

Execute a SQL query and return results as a markdown table

02

execute_query_json

Execute a SQL query and return results as JSON

03

get_table_columns

Get column names for a specific table

04

get_table_types

Get column types for a specific table

05

get_query_history

Get the recent query history

06

list_databases

List all available database connections

07

get_database_info

Get detailed information about a database including schema

08

find_table

Find which database contains a specific table

09

describe_table

Get detailed description of a table including column names and types

10

get_table_sample

Get a sample of data from a table

Installation

1. Prerequisites
• Python 3.9 or higher
• Git (to clone the repository)
• Access credentials for the target databases you plan to query (PostgreSQL, MySQL, etc.)
2. Clone the repository
git clone https://github.com/TheRaLabs/legion-mcp.git cd legion-mcp
3. Create and activate a virtual environment (recommended)
python -m venv .venv source .venv/bin/activate # Windows: .venv\Scripts\activate
4. Install server dependencies
pip install -r requirements.txt
5. (Optional) Install extra database drivers you need, e.g.
pip install psycopg2-binary # PostgreSQL pip install mysqlclient # MySQL/MariaDB
6. Configure the server
• Copy the example environment file if present: cp .env.example .env
• Set the following mandatory variables in .env or your shell:
LEGION_API_KEY = <your-legion-api-key> MCP_DATABASE_URL = <SQLAlchemy-style DB URL, e.g. postgresql://user:pass@host/db> MCP_ALLOWED_ORIGINS = <comma-separated CORS origins>
7. Launch the MCP server
python -m legion_mcp.app # or: uvicorn legion_mcp.app:app --host 0.0.0.0 --port 8000
8. Verify
Open http://localhost:8000/health or /docs (if FastAPI-style OpenAPI docs are exposed) to confirm the service is running.

Documentation

License: GNU General Public License v3.0
Updated 7/30/2025