SymDex: Open-Source MCP Code Indexer Reduces AI Agent Token Usage
What SymDex Does
SymDex addresses a specific problem with current AI coding agents: when asked to find a function, they typically read the entire file containing that function, burning through context window tokens before doing any real work. The developer built SymDex because every AI agent they used was reading entire files just to find one function.
The Token Math
According to the source material, a 300-line file contains approximately 10,500 characters. With BPE tokenizers (used by major LLMs) processing roughly 3-4 characters per token, that's about 3,000 tokens for the code, plus indentation whitespace and response framing, totaling approximately 3,400 tokens to look up one function. A real debugging session might touch 8-10 files, consuming most of the context window before any fixes are made.
How It Works
SymDex pre-indexes your codebase once. After indexing, your agent knows exactly where every function and class is without reading full files. The same 300-line file that costs ~3,400 tokens to read returns results in ~100 tokens with SymDex.
Additional features include:
- Semantic search locally (find functions by what they do, not just name)
- Call graph tracking so your agent knows what breaks before touching anything
Getting Started
Installation and basic usage:
pip install symdex
symdex index ./your-project --name myproject
symdex search "validate email"Compatibility and Licensing
SymDex works with Claude, Codex, Gemini CLI, Cursor, Windsurf, and any MCP-compatible agent. It also has a standalone CLI. The tool is free, MIT licensed, and runs entirely on your machine. It supports 12 programming languages.
📖 Read the full source: r/ClaudeAI
👀 See Also
gui.new: Tool for Claude to Render Visual Output as Shareable Links
gui.new is a tool that lets Claude render visual output as live shareable links instead of returning code blocks. It's built with Claude, uses Next.js on Vercel with Supabase, and requires no signup.
hipEngine: Fast Native Qwen 3.6 Inference for RDNA3 (Strix Halo, 7900 XTX)
hipEngine is a new open-source (AGPLv3) ROCm-native inference engine for Qwen 3.6 MoE on RDNA3 GPUs. Benchmarks show prefill up to 2718 tok/s on 7900 XTX, competitive with llama.cpp, and INT8 KV cache enabling full 256K context in under 24GB.
soul.py adds persistent memory to local LLMs with simple file-based approach
soul.py is a Python library that adds persistent memory to any LLM using two markdown files for identity and conversation logging, working with Ollama, OpenAI, and Anthropic models without requiring databases or servers.
Event Horizon VS Code Extension Adds File Locking and Plan Coordination for Multiple AI Agents
Event Horizon, a VS Code extension originally created for visualizing Claude Code, now includes file locking and plan coordination features to prevent multiple AI agents from overwriting each other's work on the same codebase. The tool supports Claude Code, OpenCode, and Copilot with one-click setup.