cxpak

Spends CPU cycles so you don't spend tokens. The LLM gets a briefing packet instead of a flashlight in a dark room.

A Rust CLI that indexes codebases using tree-sitter and produces token-budgeted context bundles for LLMs.

Installation

cargo install cxpak

Usage

# Structured repo summary within a token budget
cxpak overview --tokens 50k .

# Write output to a file
cxpak overview --tokens 50k --out context.md .

# Trace from a function/error, pack relevant code paths
cxpak trace --tokens 50k "handle_request" .

# Trace with full dependency graph traversal
cxpak trace --tokens 50k --all "MyError" /path/to/repo

# Different output formats
cxpak overview --tokens 50k --format json .
cxpak overview --tokens 50k --format xml .

What You Get

The overview command produces a structured briefing with these sections:

• Project Metadata — file counts, languages, estimated tokens
• Directory Tree — full file listing
• Module / Component Map — files with their public symbols
• Dependency Graph — import relationships between files
• Key Files — full content of README, config files, manifests
• Function / Type Signatures — every public symbol's signature
• Git Context — recent commits, file churn, contributors

Each section has a budget allocation. When content exceeds its budget, it's truncated with the most important items preserved first.

Pack Mode

When a repo exceeds the token budget, cxpak automatically switches to pack mode:

• The overview stays within budget (one file, fits in one LLM prompt)
• A .cxpak/ directory is created with full untruncated detail files
• Truncated sections in the overview get pointers to their detail files

repo/
  .cxpak/
    tree.md          # complete directory tree
    modules.md       # every file, every symbol
    dependencies.md  # full import graph
    signatures.md    # every public signature
    key-files.md     # full key file contents
    git.md           # full git history

Detail file extensions match --format: .md for markdown, .json for json, .xml for xml.

The overview tells the LLM what exists. The detail files let it drill in on demand. .cxpak/ is automatically added to .gitignore.

If the repo fits within budget, you get a single file with everything — no .cxpak/ directory needed.

Supported Languages

Rust, TypeScript, JavaScript, Python, Java, Go, C, C++, Ruby, C#, Swift, Kotlin

Tree-sitter grammars are compiled in. All 12 languages are enabled by default. Language features can be toggled:

# Only Rust and Python support
cargo install cxpak --no-default-features --features lang-rust,lang-python

License

MIT