ChunkHound

Your entire codebase, deeply understood

Multi-hop semantic search. Architecture research. Cited reports. Auto-generated documentation.

100% local · 33 languages · MIT licensed · Free forever

uv tool install chunkhound
--
“We’ve repeatedly demonstrated compressing what used to take 2–3 months down to 2–3 days. Claude Code orchestrates tens to hundreds of deep research calls over our monorepo, zooming into each subsection systematically.” — Ofir Rozenfeld, AI Transformation Product Manager at Applied Materials

AI writes code blind

Your AI agent generates code without understanding your architecture. It doesn't know that the auth middleware chains through three files, that your data model changed six months ago, or that there's already a utility for exactly what it's about to write. ChunkHound gives every AI agent deep, structured understanding of your architecture — so the first attempt is the right one.

THE APPROACH

Three lenses into one semantic index

ChunkHound parses your code with cAST — AST-aware chunking backed by Carnegie Mellon research (arXiv:2506.15655). It builds a semantic graph that search, research, and documentation all draw from. Not three separate tools — three lenses into one index.

Search Find code semantically
Research Understand architecture
Autodoc Generate documentation
One semantic index

TOKEN EFFICIENCY

A retry is just a token you didn't have to spend.

When an agent doesn't know your architecture, it guesses. When it guesses wrong, it loops — regenerating on context already polluted by the failed attempt. ChunkHound spends tokens once: a research call that surfaces the auth chain, the utility that already exists, the data model that changed last quarter. Users consistently report the same pattern across codebases of every size.

Without context

Attempt 1 — wrong direction
Attempt 2 — missed existing utility
Attempt 3 — architecture conflict
Debug loop, backtrack, re-query
Attempt 4 — done.

With ChunkHound

Research call — architecture mapped,
utilities found, patterns understood.
 
 
Attempt 1 — done.
“I would pay for ChunkHound. The code research is that good.” — @FlatTreNeb, Reddit

CAPABILITIES

Seven capabilities, one semantic index

Multi-Hop Semantic Search

Discovers code through semantic bridges. Three hops find architectural relationships that keyword search misses entirely.

3-hop traversal

Gap Detection & Filling

Clusters results, identifies missing concepts via LLM analysis, uses elbow detection to filter noise. Finds what you didn't know to ask for.

Elbow detection

cAST Chunking

AST-aware code splitting from Carnegie Mellon research. +4.3 recall on RepoEval, +2.67 pass@1 on SWE-bench vs. naive chunking.

arXiv:2506.15655

Depth Exploration

Explores different angles of files already in results. A file with auth logic and session management gets explored for both.

Aspect-based queries

Code Research

One call produces a cited markdown architecture report. Query expansion, gap detection, evidence ledger, map-reduce synthesis.

Cited reports

Unified Semantic + Regex

Extracts symbols from semantic results, runs parallel regex searches, reranks everything against the root query. Two paradigms, unified.

Hybrid search

Auto-Documentation

Generates a searchable documentation site from your codebase. Five comprehensiveness levels from minimal to exhaustive.

5 levels
“Chunkhound has been an absolute beast in reading multiple large repos in such extents that would take a human days or the plain claude code setup multiple attempts to get it (at least somewhat) right.” — @flrk, co-founder of Kimara AI

PROVEN AT SCALE

Your laptop outperforms their cluster.

Sourcegraph needs Kubernetes. Augment Code needs their servers. GitHub Copilot's @workspace tops out before your monorepo does. ChunkHound indexes your entire codebase on your own machine — no cloud account, no vendor, no code leaving your network. MIT licensed. Community built. Applied Materials runs 50M+ lines on a developer laptop today.

The alternatives ChunkHound
Kubernetes cluster required not needed
H100 / GPU server required not needed
Vendor subscription required MIT licensed
Code leaves network yes never
Closed, proprietary yes open source
Applied Materials

50M+ lines · 1 developer laptop · 0 bytes sent · MIT licensed · production today

Connect to your AI agent

Works with your agent
+ any MCP-compatible
Embedding provider
+ any OpenAI-compatible
LLM provider
echo .chunkhound.json >> .gitignore
cat > .chunkhound.json <<'CHUNKHOUND_EOF'
{
  "embedding": {
    "provider": "voyageai",
    "model": "voyage-3.5",
    "api_key": "<YOUR_VOYAGE_API_KEY>"
  },
  "llm": {
    "provider": "anthropic",
    "api_key": "<YOUR_ANTHROPIC_API_KEY>"
  }
}
CHUNKHOUND_EOF
mkdir -p .cursor
cat > .cursor/mcp.json <<'CHUNKHOUND_EOF'
{
  "mcpServers": {
    "ChunkHound": {
      "command": "chunkhound",
      "args": [
        "mcp"
      ]
    }
  }
}
CHUNKHOUND_EOF
chunkhound index .

.chunkhound.json holds your API keys

The first command adds it to .gitignore so you don't commit secrets. Replace the <YOUR_*_API_KEY> placeholders with real keys before running. Local OpenAI-compatible backends still need an explicit model. Need Azure OpenAI, a self-hosted endpoint, or a proxy?