TheRaLabs/legion-mcp

A server that helps people access and query data in databases using the Legion Query Runner with integration of the Model Context Protocol (MCP) Python SDK.
Start Generation Here
This tool is provided by Legion AI. To use the full-fledged and fully powered AI data analytics tool, please visit the site. Email us if there is one database you want us to support.
End Generation Here
Why Choose Database MCP
Database MCP stands out from other database access solutions for several compelling reasons:
- **Unified Multi-Database Interface**: Connect to PostgreSQL, MySQL, SQL Server, and other databases through a single consistent API - no need to learn different client libraries for each database type.
- **AI-Ready Integration**: Built specifically for AI assistant interactions through the Model Context Protocol (MCP), enabling natural language database operations.
- **Zero-Configuration Schema Discovery**: Automatically discovers and exposes database schemas without manual configuration or mapping.
- **Database-Agnostic Tools**: Find tables, explore schemas, and execute queries with the same set of tools regardless of the underlying database technology.
- **Secure Credential Management**: Handles database authentication details securely, separating credentials from application code.
- **Simple Deployment**: Works with modern AI development environments like LangChain, FastAPI, and others with minimal setup.
- **Extensible Design**: Easily add custom tools and prompts to enhance functionality for specific use cases.
Whether you're building AI agents that need database access or simply want a unified interface to multiple databases, Database MCP provides a streamlined solution that dramatically reduces development time and complexity.
Features
- Multi-database support - connect to multiple databases simultaneously
- Database access via Legion Query Runner
- Model Context Protocol (MCP) support for AI assistants
- Expose database operations as MCP resources, tools, and prompts
- Multiple deployment options (standalone MCP server, FastAPI integration)
- Query execution and result handling
- Flexible configuration via environment variables, command-line arguments, or MCP settings JSON
- User-driven database selection for multi-database setups
Supported Databases
| Database | DB_TYPE code |
|----------|--------------|
| PostgreSQL | pg |
| Redshift | redshift |
| CockroachDB | cockroach |
| MySQL | mysql |
| RDS MySQL | rds_mysql |
| Microsoft SQL Server | mssql |
| Big Query | bigquery |
| Oracle DB | oracle |
| SQLite | sqlite |
We use Legion Query Runner library as connectors. You can find more info on their api doc.
What is MCP?
The Model Context Protocol (MCP) is a specification for maintaining context in AI applications. This server uses the MCP Python SDK to:
- Expose database operations as tools for AI assistants
- Provide database schemas and metadata as resources
- Generate useful prompts for database operations
- Enable stateful interactions with databases
Installation & Configuration
Required Parameters
For single database configuration:
- **DB_TYPE**: The database type code (see table above)
- **DB_CONFIG**: A JSON configuration string for database connection
For multi-database configuration:
- **DB_CONFIGS**: A JSON array of database configurations, each containing:
- **db_type**: The database type code