TreeSitter MCP Server

A fast Model Context Protocol (MCP) server that analyzes source code files and extracts their structure in a markdown format optimized for LLM consumption.

Features

• Multi-language Support: Python, JavaScript, TypeScript, Java, C#, and Go
• Fast Parsing: Uses tree-sitter for efficient AST parsing
• Comprehensive Structure: Extracts classes, functions, nested elements
• Line Numbers: Tracks start and end lines for each element
• Nesting Levels: Shows the depth of nested elements
• Parameters & Return Types: Extracts function signatures
• Optional Docstrings: Configurable docstring extraction
• Multi-File Analysis: Analyze single or multiple files in one request
• Error Handling: Parses as much as possible and indicates error locations
• LLM-Optimized Output: Markdown format designed for easy LLM consumption

Installation

Using uv (Recommended)

uv sync

Using pip

pip install -r requirements.txt

Usage

Running the MCP Server

uv run python src/server.py

Or directly:

python src/server.py

MCP Configuration

Add the following to your MCP client configuration (e.g., Claude Desktop):

{
  "mcpServers": {
    "CodeStructureAnalyzer": {
      "command": "uv",
      "args": [
        "--directory",
        "/path/to/TreeSitterMcp",
        "run",
        "python",
        "src/server.py"
      ]
    }
  }
}

MCP Tool: query

Analyzes the structure of one or more source code files.

Parameters:

• file_path (required): Path to the source code file(s) to analyze. Can be either:
  • A single file path as a string (e.g., "src/models.py")
  • An array of file paths (e.g., ["src/models.py", "src/config.py"])
• include_docstrings (optional, default: false): Whether to include docstrings in the output

Single File Analysis

Example Request:

{
  "name": "query",
  "arguments": {
    "file_path": "src/models.py",
    "include_docstrings": true
  }
}

Multi-File Analysis

Example Request:

{
  "name": "query",
  "arguments": {
    "file_path": ["src/models.py", "src/config.py", "src/server.py"],
    "include_docstrings": false
  }
}

Output Format

The output is optimized for token efficiency and follows this schema: Format: ### Name (Start-End, Nesting, [Parent]) | - Type | - [Parameters] | - [Return Type] | - [Docstring]

Example Output:

Format: ### `Name` (Start-End, Nesting, [Parent]) | - Type | - [Parameters] | - [Return Type] | - [Docstring]

# `src/models.py`

### `MyClass` (10-50, N:0)
- Class
- A sample class for demonstration.

  ### `__init__` (15-25, N:1, P: `MyClass`)
  - Function
  - (self, param1: str, param2: int)
  - -> None
  - Initialize the class.

Multi-File Output Example

Format: ### `Name` (Start-End, Nesting, [Parent]) | - Type | - [Parameters] | - [Return Type] | - [Docstring]

# `src/models.py`

### `MyClass` (10-50, N:0)
- Class
...

---
# `src/config.py`

### `get_language_from_extension` (10-20, N:0)
- Function
...

Supported Languages

Language	File Extensions
Python	.py
JavaScript	.js, .mjs, .cjs
TypeScript	.ts, .tsx
Java	.java
C#	.cs
Go	.go

Architecture

The server is organized into the following modules:

• src/mcp_impl/server.py: MCP server implementation with tool definitions
• src/parsers/tree_sitter.py: Tree-sitter parser integration
• src/extractors/structure.py: Code structure extraction logic
• src/formatters/markdown.py: Markdown formatting for output
• src/config.py: Language configuration and mappings
• src/models.py: Data models for code elements

Error Handling

The server attempts to parse as much of the file as possible, even when there are syntax errors. Errors are reported in a dedicated section:

## Parse Errors

⚠️ **Error at Line 42**: Syntax error

return self.process(item

Development

Running Tests

uv run pytest

Code Formatting

uv run black src/

Type Checking

uv run mypy src/

License

MIT License

Contributing

Contributions are welcome! Please feel free to submit a Pull Request.