mcp-datahub: Instructions file for Claude Code

CLAUDE.md

This file provides guidance to Claude Code when working with this project.

Project Overview

mcp-datahub is a composable Go library for building custom MCP (Model Context Protocol) servers that integrate DataHub metadata capabilities. It is part of the txn2 MCP toolkit ecosystem alongside mcp-trino.

Project Positioning

This is NOT a replacement for the official DataHub MCP server. This library serves a different purpose:

1. Primary Use: A composable building block for creating unified MCP servers that combine multiple data tools (DataHub + Trino + dbt + custom tools) into a single AI assistant interface.

2. Secondary Use: The included mcp-datahub binary is a reference implementation that demonstrates library capabilities—functional as a standalone DataHub MCP server.

Key Design Principles

• Composable: Designed to work alongside other MCP toolkits (mcp-trino, etc.)
• Library-first: The CLI binary is a reference implementation, not the primary deliverable
• Extensible: Middleware system for adding auth, audit logging, rate limiting
• Island architecture: No dependencies on other txn2 libraries
• Generic: No domain-specific logic; suitable for any DataHub deployment

Architecture

pkg/
├── client/      # DataHub GraphQL client (standalone, no MCP dependency)
├── multiserver/ # Multi-server configuration and connection management
├── types/       # Domain types (entities, schema, lineage, etc.)
├── tools/       # MCP toolkit (composable tool registration)
├── integration/ # Extension interfaces for custom integrations
└── extensions/  # Optional middleware: logging, metrics, error hints, config files

internal/
└── server/      # Reference implementation server setup

cmd/
└── mcp-datahub/ # Reference implementation CLI binary

mcpb/
├── manifest.json # MCPB bundle manifest for Claude Desktop
└── build.sh      # Build script for .mcpb bundles

Composition Pattern