symgraph

Semantic code intelligence MCP server - build knowledge graphs of codebases to enhance AI-assisted code exploration.

symgraph is a rust implementation of https://github.com/colbymchenry/codegraph. Why? Ongoing exploration of compiled binary deployment of MCP Servers.

Features

• Multi-language support: Rust, TypeScript, JavaScript, Python, Go, Java, C, C++
• Symbol extraction: functions, classes, methods, structs, interfaces, traits, enums, constants
• Relationship tracking: calls, contains, imports, exports, extends, implements
• Impact analysis: trace the effect of changes through the codebase
• Advanced code intelligence:
  • Find call paths between functions
  • Detect unused/dead code
  • Explore class hierarchies
  • Locate all interface implementations
  • Analyze change impact by line range
• Incremental indexing: only re-indexes changed files using content hashing
• Dual transport: stdio (default) and HTTP server modes

Installation

macOS & Linux

curl -fsSL https://raw.githubusercontent.com/grahambrooks/symgraph/main/install.sh | bash

To also configure symgraph as an MCP server for Claude Code and Claude Desktop:

curl -fsSL https://raw.githubusercontent.com/grahambrooks/symgraph/main/install.sh | bash -s -- --mcp

Install a specific version:

SYMGRAPH_VERSION=2026.3.30 curl -fsSL https://raw.githubusercontent.com/grahambrooks/symgraph/main/install.sh | bash

Windows (PowerShell)

irm https://raw.githubusercontent.com/grahambrooks/symgraph/main/install.ps1 -OutFile install.ps1; .\install.ps1

To also configure symgraph as an MCP server for Claude Code and Claude Desktop:

irm https://raw.githubusercontent.com/grahambrooks/symgraph/main/install.ps1 -OutFile install.ps1; .\install.ps1 -Mcp

Install a specific version:

$env:SYMGRAPH_VERSION="2026.3.30"; irm https://raw.githubusercontent.com/grahambrooks/symgraph/main/install.ps1 -OutFile install.ps1; .\install.ps1

Both scripts install to ~/.symgraph/bin/ by default. Override with SYMGRAPH_INSTALL_DIR.

Claude Desktop (MCPB Bundle)

Download and install the MCPB bundle for your platform:

1. Download the .mcpb file for your platform from Releases
2. Open Claude Desktop
3. Drag and drop the .mcpb file onto Claude Desktop, or use File > Install MCP Server
4. Configure the project root when prompted

From Source

git clone https://github.com/grahambrooks/symgraph
cd symgraph
make install

Usage

Index a Codebase

# Index current directory
symgraph index

# Index specific directory
symgraph index ~/projects/myapp

Start MCP Server

# Start with stdio transport (for Claude Desktop)
symgraph serve

# Start with HTTP transport
symgraph serve --port 8080

CLI Commands

symgraph index [path]           # Index a codebase
symgraph serve                  # Start MCP server (stdio)
symgraph serve --port <PORT>    # Start MCP server (HTTP)
symgraph status [path]          # Show index statistics
symgraph search <query>         # Search for symbols
symgraph context <task>         # Build context for a task

MCP Tools

Core Tools

Advanced Tools

Example Use Cases

Find dead code for cleanup:

Use symgraph-unused to find all unused functions and classes

Understand function call chains:

Use symgraph-path with from="main" and to="database_query" to see how data flows

Assess change impact:

Use symgraph-diff-impact with file_path="src/auth.rs" start_line=45 end_line=60
to see what would be affected by changes in that region

Explore OOP hierarchies:

Use symgraph-hierarchy with symbol="BaseHandler" to see all parent/child relationships

Find all trait implementations:

Use symgraph-implementations with symbol="Iterator" to find all structs implementing Iterator

Project Setup

Add symgraph to your project in two steps: index your code, then configure your AI tool.

Step 1: Index Your Project

cd /path/to/your/project
symgraph index

This creates a .symgraph/ directory containing the SQLite knowledge graph. Add .symgraph/ to your .gitignore.

Re-run symgraph index after significant code changes, or use the symgraph-reindex MCP tool to incrementally update from within your AI tool.

Step 2: Configure Your AI Tool

Claude Code

Register symgraph as an MCP server for your project:

cd /path/to/your/project
claude mcp add symgraph -- symgraph serve

Or add .mcp.json to your project root:

{
  "mcpServers": {
    "symgraph": {
      "type": "stdio",
      "command": "symgraph",
      "args": ["serve"]
    }
  }
}

Optional: Add the /explore-code skill for guided code exploration:

mkdir -p .claude/skills
cp -r /path/to/symgraph/.claude/skills/explore-code .claude/skills/

Then use it in Claude Code:

/explore-code how does the authentication middleware work?
/explore-code what would break if I changed the User struct?

Claude Desktop

Via MCPB bundle (easiest):

1. Download the .mcpb file for your platform from Releases
2. Drag and drop onto Claude Desktop, or use File > Install MCP Server
3. Set the project root when prompted

Via manual config — add to claude_desktop_config.json:

{
  "mcpServers": {
    "symgraph": {
      "command": "symgraph",
      "args": ["serve"],
      "env": {
        "SYMGRAPH_ROOT": "/path/to/your/project"
      }
    }
  }
}

GitHub Copilot

Per-repository — add .copilot/mcp.json to your project:

{
  "mcpServers": {
    "symgraph": {
      "command": "symgraph",
      "args": ["serve"]
    }
  }
}

VS Code user settings — add to settings.json:

{
  "github.copilot.chat.mcp.servers": {
    "symgraph": {
      "command": "symgraph",
      "args": ["serve"],
      "env": {
        "SYMGRAPH_ROOT": "${workspaceFolder}"
      }
    }
  }
}

See GitHub Copilot MCP documentation for more details.

OpenAI Codex

codex mcp add symgraph --command "symgraph" --args "serve"

Or add to ~/.codex/config.toml:

[mcp_servers.symgraph]
command = "symgraph"
args = ["serve"]

See OpenAI Codex MCP documentation for more details.

HTTP Mode (Any MCP Client)

For shared or remote setups, run symgraph as an HTTP server:

symgraph serve --port 8080

Then point your MCP client at http://localhost:8080/mcp.

Environment Variables

Architecture

symgraph/
├── src/
│   ├── main.rs          # CLI entry point
│   ├── lib.rs           # Core indexing logic
│   ├── types.rs         # Type definitions (Node, Edge, etc.)
│   ├── db/              # SQLite database operations
│   ├── extraction/      # Tree-sitter code extraction
│   ├── graph/           # Graph traversal algorithms
│   ├── context/         # Context building for AI tasks
│   └── mcp/             # MCP protocol handlers
└── .symgraph/
    └── index.db         # SQLite database (per-project)

Core Concepts

• Node: A code symbol (function, class, method, etc.)
• Edge: A relationship between nodes (calls, contains, imports, etc.)
• Knowledge Graph: The complete set of nodes and edges for a codebase

Development

Prerequisites

• Rust 1.70+
• SQLite (bundled via rusqlite)

Building

make build           # Release build
make test            # Run tests
make check           # Format, lint, and test
make install         # Build and install to /usr/local/bin

Project Structure

License

MIT