Semgrep MCP server for AI agents

The Semgrep MCP Server allows you to perform static code analysis and manage Semgrep rules directly through the Model Context Protocol. It integrates Semgrep functionality into your development environment, making it easier to conduct security and quality scans of your codebase.

Installation

To install the Semgrep MCP Server:

# Clone the repository
git clone [repository-url]
cd semgrep-server

# Install dependencies
npm install

# Build the server
npm run build

Running the Server

You can start the server using one of the following commands:

# Production mode
npm start

# Development mode
npm run dev

Available Tools

The server provides several MCP tools that you can utilize:

Scanning and Analysis

scan_directory: Executes a Semgrep scan on a specified directory
analyze_results: Analyzes the scan results
filter_results: Filters scan results based on various criteria
compare_results: Compares two scan results

Rule Management

list_rules: Shows available Semgrep rules
create_rule: Creates a new Semgrep rule

Exporting

export_results: Exports scan results to different formats

Usage Examples

Running a Scan

To scan a directory for vulnerabilities or code quality issues:

# Example of calling the scan_directory tool via MCP
# (The exact command depends on your MCP client implementation)

Working with Rules

To list all available rules:

# Example of calling the list_rules tool via MCP

To create a new rule:

# Example of calling the create_rule tool via MCP

Managing Scan Results

Filter results to show only high-severity issues:

# Example of calling the filter_results tool via MCP

Export results to a shareable format:

# Example of calling the export_results tool via MCP

Compare results from different scans:

# Example of calling the compare_results tool via MCP

How to install this MCP server

For Claude Code

To add this MCP server to Claude Code, run this command in your terminal:

claude mcp add-json "semgrep" '{"command":"npx","args":["semgrep-server"]}'

See the official Claude Code MCP documentation for more details.

For Cursor

There are two ways to add an MCP server to Cursor. The most common way is to add the server globally in the ~/.cursor/mcp.json file so that it is available in all of your projects.

If you only need the server in a single project, you can add it to the project instead by creating or adding it to the .cursor/mcp.json file.

Adding an MCP server to Cursor globally

To add a global MCP server go to Cursor Settings > Tools & Integrations and click "New MCP Server".

When you click that button the ~/.cursor/mcp.json file will be opened and you can add your server like this:

{
    "mcpServers": {
        "semgrep": {
            "command": "npx",
            "args": [
                "semgrep-server"
            ]
        }
    }
}

Adding an MCP server to a project

To add an MCP server to a project you can create a new .cursor/mcp.json file or add it to the existing one. This will look exactly the same as the global MCP server example above.

How to use the MCP server

Once the server is installed, you might need to head back to Settings > MCP and click the refresh button.

The Cursor agent will then be able to see the available tools the added MCP server has available and will call them when it needs to.

You can also explicitly ask the agent to use the tool by mentioning the tool name and describing what the function does.

For Claude Desktop

To add this MCP server to Claude Desktop:

1. Find your configuration file:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json
Windows: %APPDATA%\Claude\claude_desktop_config.json
Linux: ~/.config/Claude/claude_desktop_config.json

2. Add this to your configuration file:

{
    "mcpServers": {
        "semgrep": {
            "command": "npx",
            "args": [
                "semgrep-server"
            ]
        }
    }
}

3. Restart Claude Desktop for the changes to take effect