Serena
Powerful free AI coding agent toolkit providing semantic code retrieval, intelligent editing, and language server integration as an alternative to expensive coding assistants.
Author: oraios | GitHub Repo | 3165 Stars|238 Forks|MIT License|Updated Jun 29, 2025
Overview
Serena is a comprehensive AI coding agent toolkit that provides semantic code understanding and intelligent editing capabilities through language server integration. Designed as a free alternative to expensive coding assistants like Cursor and Windsurf, it offers symbol-level code comprehension, multi-language support, and advanced project analysis through MCP integration with Claude Code and other AI platforms.
Features
- Semantic Code Retrieval - Advanced code understanding through language server integration and symbol analysis
- Symbol-Level Intelligence - Function, class, and variable level comprehension across codebases
- Multi-Language Support - Works with Python, JavaScript, TypeScript, Rust, Go, and 8+ programming languages
- IDE-Like Functionality - Provides IDE-level features through AI interaction without complex setup
- MCP Integration - Seamless integration with Claude Code and other MCP-compatible AI clients
- Free & Open Source - No subscription fees or usage limits, community-driven development
Installation
Prerequisites
- Python 3.11+ (specifically, not 3.12+) with uv package manager
- Git for repository cloning
- Language servers for target programming languages (auto-installed)
- Claude Code or compatible MCP client
Recommended Installation (UVX)
# Direct execution from GitHub (recommended for MCP)
# Windows:
uvx --from git+https://github.com/oraios/serena serena-mcp-server.exe
# Linux/macOS:
uvx --from git+https://github.com/oraios/serena serena-mcp-server
MCP Configuration
{
"mcpServers": {
"serena": {
"command": "uvx",
"args": [
"--from",
"git+https://github.com/oraios/serena",
"serena-mcp-server"
]
}
}
}
Alternative: Local Development Setup
# 1. Clone the repository (REQUIRED)
git clone https://github.com/oraios/serena
cd serena
# 2. Optional: Copy configuration template
cp src/serena/resources/serena_config.template.yml serena_config.yml
# 3. Run the MCP server
uv run serena-mcp-server
For Local Installation MCP Configuration
{
"mcpServers": {
"serena": {
"command": "/absolute/path/to/uv",
"args": [
"run",
"--directory",
"/absolute/path/to/serena",
"serena-mcp-server"
]
}
}
}
Language Server Setup
# Serena automatically installs language servers for:
# Python (pylsp), JavaScript/TypeScript (typescript-language-server)
# Rust (rust-analyzer), Go (gopls), and 8+ other languages
# No manual configuration required
Usage
Semantic Code Analysis
# Example AI interactions through Claude Code:
# "Analyze the authentication flow in this project"
# "Find all functions that handle user data validation"
# "Explain the relationship between these classes"
# "Refactor this module to improve separation of concerns"
Serena provides deep code understanding that goes beyond simple text analysis. It comprehends code structure, relationships, and semantics through language server integration, enabling sophisticated code analysis and intelligent editing suggestions through natural language interaction.
Advanced Capabilities
- Project Understanding: Analyze entire codebases and understand architectural patterns
- Intelligent Editing: Make precise code changes based on semantic understanding
- Cross-Reference Analysis: Track function calls, imports, and dependencies
- Code Quality Assessment: Identify potential issues and improvement opportunities
Serena is developed by oraios and is open-source. For technical support, language server configuration, and community contributions, please refer to the official GitHub repository.