TreeMapper

Smart diff context for LLM code review. Selects the minimal set of code fragments needed to understand a git change — instead of dumping entire files.

Also exports full codebase structure + contents in YAML/JSON/MD/txt. Works with any LLM. 100% local, free, no GitHub dependency.

pipx install treemapper

treemapper . --diff HEAD~1       # smart context for last commit → paste into Claude/ChatGPT
treemapper . -f md -c           # full export → clipboard in Markdown

Why not just use tree or repomix?

	tree	repomix	Claude Code Review	TreeMapper
Primary use case	directory listing	full repo export	automated PR review	diff context for code review
Smart diff context	✗	✗	✓	✓
Works with any LLM	✓	✓	Claude only	✓
Free / local / offline	✓	✓	$15–25/review	✓
GitHub required	✗	✗	✓	✗
Multiple output formats	✗	limited	—	YAML/JSON/MD/txt
Python API	✗	✗	✗	✓

Installation

pipx install treemapper                    # recommended: isolated, no venv needed
pip install treemapper                     # or with pip
pip install 'treemapper[tree-sitter]'      # + AST parsing for smarter diff context

Standalone binary (no Python required): download from the releases page.

Diff context mode works out of the box. Adding [tree-sitter] enables AST-level parsing for more accurate context selection across 12 languages.

Diff Context Mode

Paper: Context-Selection for Git Diff (Zenodo, 2026)

Automatically finds the minimal set of code fragments needed to understand a change — imports, callers, type definitions, config dependencies — without dumping entire files. Understands 50+ file types.

name: myproject
type: diff_context
fragment_count: 5
fragments:
  - path: src/main.py
    lines: "10-25"
    kind: function
    symbol: process_data
    content: |
      def process_data(items):
          ...

How it works

Uses Personalized PageRank on a code graph (imports, co-changes, type refs) to propagate relevance from changed lines outward. Stops when signal decays below threshold τ, or at an explicit --budget token limit.

Flag	Default	Description
--budget	none	Token limit (convergence-based by default)
--full	false	Include all changed code, skip selection
--alpha	0.60	PPR damping factor
--tau	0.08	Convergence threshold

Usage

# full codebase export:
treemapper .                                # YAML to stdout + token count
treemapper . -f md -c                       # Markdown → clipboard
treemapper . -f json -o tree.json           # JSON → file
treemapper . --no-content                   # structure only, no file contents
treemapper . --max-depth 3                  # limit depth
treemapper . -i custom.ignore               # custom ignore patterns

# diff context mode (requires git repo):
treemapper . --diff HEAD~1                  # context for last commit
treemapper . --diff main..feature           # context for feature branch
treemapper . --diff HEAD~1 --budget 30000   # limit to ~30k tokens
treemapper . --diff HEAD~1 -c               # diff context to clipboard

Full codebase export output format:

name: myproject
type: directory
children:
  - name: main.py
    type: file
    content: |
      def hello():
          print("Hello, World!")
  - name: utils/
    type: directory
    children:
      - name: helpers.py
        type: file
        content: |
          def add(a, b):
              return a + b

Token Counting

Token count and size are always displayed on stderr:

12,847 tokens (o200k_base), 52.3 KB

For large outputs (>1MB), approximate counts with ~ prefix:

~125,000 tokens (o200k_base), 5.2 MB

Uses tiktoken with o200k_base encoding (GPT-4o tokenizer).

Clipboard Support

Copy output directly to clipboard with -c or --copy:

treemapper . -c                       # copy (stdout suppressed, stderr: token count)
treemapper . -c -o tree.yaml          # copy + save to file

System Requirements:

• macOS: pbcopy (pre-installed)
• Windows: clip (pre-installed)
• Linux (Wayland): wl-copy
• Linux (X11): xclip or xsel

Python API

from treemapper import map_directory
from treemapper import to_yaml, to_json, to_text, to_markdown

tree = map_directory(
    path,                     # directory path
    max_depth=None,           # limit traversal depth
    no_content=False,         # exclude file contents
    max_file_bytes=None,      # skip large files
    ignore_file=None,         # custom ignore file
    no_default_ignores=False, # disable default ignores
    whitelist_file=None,      # include-only filter
)

yaml_str = to_yaml(tree)
json_str = to_json(tree)
text_str = to_text(tree)
md_str = to_markdown(tree)

# Diff context mode
from treemapper import build_diff_context

ctx = build_diff_context(
    root_dir,                 # Path to repository root
    diff_range,               # e.g. "HEAD~1..HEAD", "main..feature"
    budget_tokens=None,       # token limit (None = convergence-based)
    alpha=0.6,                # PPR damping factor
    tau=0.08,                 # stopping threshold
    full=False,               # skip smart selection
)
yaml_str = to_yaml(ctx)

Ignore Patterns

Respects .gitignore and .treemapper/ignore automatically. Use --no-default-ignores to disable built-in patterns (.gitignore and .treemapper/ignore still apply).

• Hierarchical: nested ignore files at each directory level
• Negation patterns: !important.log un-ignores a file
• Anchored patterns: /root_only.txt matches only in root
• Output file is always auto-ignored

Auto-discovered files:

• .treemapper/ignore — TreeMapper-specific ignore patterns
• .treemapper/whitelist — Include-only filter (only matched files included)

Content Placeholders

• <file too large: N bytes> — exceeds --max-file-bytes
• <binary file: N bytes> — binary file detected
• <unreadable content: not utf-8> — not valid UTF-8
• <unreadable content> — permission denied or I/O error

License

Apache 2.0