Serena is a production-grade MCP (Model Context Protocol) server that provides AI coding agents with deep code intelligence across 40+ programming languages. It acts as an 'IDE for your agent', offering symbol-level retrieval, editing, refactoring, and debugging capabilities by orchestrating Language Server Protocol (LSP) backends. The system is designed to integrate with AI clients like Claude Code, Codex, Copilot, and Grok, exposing a rich set of tools for file manipulation, symbol navigation, memory persistence, and project configuration. Architecturally, Serena is a Python application with a CLI entry point that starts an MCP server, a Flask-based web dashboard for monitoring and configuration, and a hooks system for client-side pre-tool-use events. Its core is the `solidlsp` package, a custom synchronous LSP abstraction layer that manages the lifecycle of 40+ language servers (Python, TypeScript, Rust, Go, Java, etc.), handling initialization, capability negotiation, and request/response framing. The `interprompt` library provides a sandboxed Jinja templating engine for prompt generation, and the memory manager persists project-specific context across sessions. Key features include: multi-language symbol search, references, definitions, hover, rename, and diagnostics; a code editor abstraction supporting both LSP and JetBrains backends; a configurable tool registry with automatic discovery; and a comprehensive test suite with per-language integration tests. The project emphasizes reproducibility through pinned dependency versions and SHA256 verification for downloaded language server binaries, though this creates a maintenance burden as versions must be manually updated.