🧠 memory_graph_mcp

An MCP server that gives your AI agent a persistent knowledge graph of your project.

TypeScript MCP Tests License Node

AST dependencies · DB-schema links · debugging sessions · side effects

💡 Why

When a feature is requested, the agent receives a dependency subgraph, not a list of similar files — protecting adjacent modules from breaking changes.

graph_query_context("src/api/users.ts")

┌─────────────────┐     imports      ┌─────────────────┐
│  src/db/users.ts │ ◄────────────── │ src/api/users.ts │
└────────┬────────┘                  └─────────────────┘
         │ writes_table
         ▼
   [table: users]   ◄── also touched by 2 other files

Instead of "here are 5 files matching users" the agent learns: changing this file affects two other modules, writes to the users table, and a past debug session recorded a missing await bug here.

🛠 Tools

Tool	Purpose
`graph_query_context`	file/symbol → dependency subgraph + adjacent modules + related sessions
`graph_impact_analysis`	planned change → affected nodes, tables, and risk level
`graph_get_side_effects`	implicit module effects: table reads/writes, calls
`graph_record_session`	record a discussion/debug session with decisions and bugs, linked to files
`graph_stats`	index state: nodes, edges, files, last update time

📦 Installation

Requires Node.js ≥ 18

git clone git@github.com:FuryCow/memory_graph_mcp.git
cd memory_graph_mcp
npm install
npm run build

🔌 Connecting

The server communicates over stdio. Set the root of the project you want to index as the working directory (cwd) in your MCP client config — the index is built from process.cwd() and stored in .memory-graph/graph.db.

Claude Desktop / Cursor

The configuration is identical for both clients; only the config file location differs:

Claude Desktop: claude_desktop_config.json (menu → Settings → Developer → Edit Config)
Cursor: ~/.cursor/mcp.json

{
  "mcpServers": {
    "memory-graph": {
      "command": "node",
      "args": ["/absolute/path/to/memory_graph_mcp/dist/src/index.js"],
      "cwd": "/absolute/path/to/your/project"
    }
  }
}

💡 On Windows, escape paths (C:\\path\\to\\...) or use forward slashes (C:/path/to/...).

🗺 Graph model


Nodes	`File`, `Symbol`, `Table` — journal: `Session`, `Decision`, `Bug`
Edges	`imports`, `calls`, `contains`, `reads_table`, `writes_table`

The indexer (tree-sitter) extracts imports, function definitions and calls, and database access from SQL strings (SELECT/INSERT/UPDATE/DELETE) and ORM patterns (Prisma, drizzle). A watcher (chokidar) incrementally re-indexes the graph on file changes — typically under a second.

🧰 Stack

Layer	Technology
Server	`@modelcontextprotocol/sdk` (stdio)
Parsing	`tree-sitter` (TypeScript / TSX / JavaScript)
Storage	`better-sqlite3` (WAL) in `.memory-graph/graph.db`
Watching	`chokidar` (mtime-based incremental re-index)

🚀 Development

npm run build   # tsc
npm test        # node --test dist/test/*.test.js
npm run lint    # tsc --noEmit

📄 License

MIT

memory_graph_mcp