arachna 1.5.3

Context collector for AI — gathers project files into token-limited chunks

arachna

Context collector for AI — gathers project files into token-limited chunks.

What I believe

I'm a solo developer building tools for myself. arachna is an indie project — not a startup, not a company, not a product for sale. Free software. AGPLv3.

I believe AI tools should be independent. Not tied to a specific editor, cloud provider, or way of working. arachna doesn't lock you in. It prepares your project for AI to understand. The rest is up to you.

• Any editor. Vim, VS Code, Cursor, Emacs — arachna doesn't care where you write code
• Any LLM. Local models, cloud APIs, web chats — the brain is your choice
• Plain files. No databases, no daemons, no hidden state. Everything is transparent — you can cat, grep, diff the output
• No telemetry. No tracking, no cloud sync, no phoning home. Your code stays on your machine
• Zero dependencies. Just Python 3.11+ stdlib. pip install arachna, that's it
• Free software, not just open source. AGPLv3 guarantees the four freedoms. No proprietary forks. What's the difference?

Contents

• What arachna does
• Install
• Quick start
• Examples
• Commands
• Options
• Profiles
• Split modes
• All config fields
• Output
• Manifest and cleanup
• Incremental mode
• Safety
• Doctor
• Git hooks (optional)
• Tokenizer
• Supported project types
• Links
• License

What arachna does

arachna collects your project files into files ready to be sent to an AI. It understands tokens (not lines) and splits output smartly so nothing gets cut in the middle.

Install

pip install arachna

Quick start

cd your-project
arachna --init
arachna --all

Creates arachna_context/ with .md files ready for AI.

Examples

Local model (Ollama)

arachna --profile code
cat arachna_context/chat-code.md | ollama run qwen2.5:32b

Cloud API (OpenAI)

arachna --profile code
# Then paste arachna_context/chat-code.md into chat.openai.com
# Or use the API:
curl https://api.openai.com/v1/chat/completions \
  -H "Authorization: Bearer $OPENAI_API_KEY" \
  -d '{"messages": [{"role": "user", "content": "'"$(cat arachna_context/chat-code.md)"'"}]}'

Multiple profiles for different tasks

# Give code to the Programmer agent
arachna --profile code

# Give tests to the Tester agent
arachna --profile tests

# Give docs to the Auditor agent
arachna --profile docs

# Give git history for context
arachna --profile git

Incremental mode (only changed files)

arachna --profile code --incremental
# First run: collects everything
# Second run: skips unchanged files, creates nothing

Dry-run (preview without writing)

arachna --all --dry-run

Safety check

arachna --validate
# Checks config for errors, exits 1 if problems found

Commands

arachna --init              interactive setup
arachna --init --defaults   auto-detect everything
arachna --init --preset X   use specific preset
arachna --all               collect all profiles
arachna --profile code      collect one profile
arachna --all --dry-run     preview without writing
arachna --clean             remove collected files
arachna --list              show profiles
arachna --validate          check config for errors
arachna --doctor            run full diagnostic
arachna --install-hook      install post-commit git hook (optional)

Options

Option	Description
--output-dir path	where to write (default: arachna_context/)
--verbose	show skipped files
--compress	remove blank lines and trailing spaces
--incremental	only files changed since last run
--format xml,json	markdown (default), xml, or json
--merge	append to existing output instead of replacing
--dry-run	preview without writing files
--force	force overwrite with --install-hook

Profiles

Profiles let you separate context by role — different context for different AI tasks.

Example .arachna.json for a Python project:

{
  "project_name": "MyProject",
  "profiles": {
    "code": {
      "split_mode": "by_file",
      "directories": ["src", "app"],
      "patterns": ["*.py"],
      "files": ["pyproject.toml", "requirements.txt"],
      "pre_commands": ["tree src app"],
      "max_tokens": 16000
    },
    "tests": {
      "split_mode": "by_file",
      "directories": ["tests"],
      "patterns": ["*.py"],
      "max_tokens": 16000
    },
    "docs": {
      "split_mode": "by_file",
      "files": ["README.md", "TODO.md", "CHANGELOG.md"],
      "max_tokens": 16000
    },
    "git": {
      "split_mode": "by_marker",
      "split_marker": "\n=== COMMIT:",
      "command": "git log --reverse --format='=== COMMIT: %h ===%nTITLE: %s%n%nMESSAGE:%n%b%n'",
      "max_tokens": 16000
    }
  }
}

Split modes

• by_file: code and docs, each file stays intact (default)
• by_paragraph: logs, splits on blank lines
• by_marker: git history, splits on custom marker
• single: everything in one file, truncates if too big

All config fields

• split_mode: by_file, by_paragraph, by_marker, or single
• split_marker: string for by_marker mode
• directories: folders to scan
• patterns: glob patterns like ["*.py"]
• files: specific files to include
• exclude_patterns: glob patterns to skip
• pre_commands: shell commands before collection
• post_commands: shell commands after collection
• command: use command output instead of files
• max_tokens: token limit per output file
• section_format: markdown, xml, or json
• compress: safe whitespace compression (blank lines, trailing spaces). Does not modify indentation
• include_binary: include binaries as base64 (true/false)
• binary_extensions: whitelist like [".png"]
• binary_max_mb: max binary file size in MB

Output

Files go to arachna_context/ (configurable):

arachna_context/
  .arachna_manifest.json
  chat-manifest.md          # summary of all files
  chat-code.md
  chat-tests.md
  chat-docs.md
  chat-git.md

When content exceeds max_tokens, files are numbered: chat-code_1.md, chat-code_2.md...

Manifest and cleanup

Every created file is tracked in .arachna_manifest.json. Running --all again removes old files automatically. With --profile, only that profile's files are cleaned.

Incremental mode

With --incremental, arachna skips files unchanged since last run. Uses .arachna_cache.json with mtime + SHA256 hashes. This is a cache for speed — not the same as Watch+Diff for agent sessions (coming in v1.6.0).

Safety

Commands in .arachna.json (pre_commands, post_commands, command) are validated before execution. Unknown or dangerous commands are blocked. The command allowlist is strictly read-only — no interpreters, no filesystem modification. Use --dry-run to preview what will be executed.

Doctor

arachna --doctor runs a full diagnostic — validates all profiles, checks that directories and files exist, verifies .gitignore integration.

Git hooks (optional)

If you prefer git-based workflow, arachna can integrate via post-commit hooks. But it works fine without git.

arachna --install-hook

Configure the command in .arachna.json:

{
  "hook": {
    "post-commit": "arachna --all --incremental"
  }
}

Tokenizer

arachna uses a conservative estimate: 4 characters = 1 token. Works for any model with a 20-30% safety margin.

Built-in (default)

No dependencies. Always works. Set max_tokens below your model's context window:

• 8192 window → max_tokens: 6000
• 32768 window → max_tokens: 24000

Custom tokenizer

Add to your .arachna.json:

  "tokenizer": "my_module:count_tokens"

Your module must export count_tokens(text) -> int:

# my_tok.py
def count_tokens(text: str) -> int:
    return max(1, len(text) // 4)  # your logic here

Cloud models

For exact token counts, install tiktoken:

pip install tiktoken

  "tokenizer": "tiktoken:cl100k_base"    # GPT-4, DeepSeek
  "tokenizer": "tiktoken:o200k_base"     # GPT-4o

Local models

For HuggingFace tokenizers, install transformers:

pip install transformers

  "tokenizer": "transformers:Qwen/Qwen2.5-7B-Instruct"
  "tokenizer": "transformers:mistralai/Mistral-7B-Instruct-v0.3"
  "tokenizer": "transformers:google/gemma-7b"

Note: transformers is a heavy dependency. For most local models, the built-in estimate with safety margin is sufficient.

Supported project types

arachna --init auto-detects 17 project types:

Languages

• Python: src/, app/, lib/, pkg/, scripts/, *.py, pyproject.toml
• JavaScript/TypeScript: src/, app/, lib/, *.js, *.ts, package.json
• C/C++: src/, include/, *.c, *.cpp, *.h, CMakeLists.txt
• C#: *.cs, *.csproj, *.sln
• Swift: Sources/, *.swift, Package.swift
• Kotlin/Java: src/, *.kt, *.java, build.gradle, pom.xml
• Ruby: lib/, app/, *.rb, Gemfile
• PHP: src/, app/, public/, *.php, composer.json

Engines

• Godot: *.gd, *.tscn, *.tres, project.godot
• Unity: Assets/, *.cs, *.unity, *.prefab
• Unreal Engine: Source/, Content/, *.cpp, *.h, *.cs, *.uproject, *.uplugin

Infrastructure

• Docker: Dockerfile, docker-compose.yml
• Terraform: *.tf, *.tfvars

Service

• tests: tests/, test/
• docs: docs/, README.md, TODO.md, CHANGELOG.md, Makefile
• config: pyproject.toml, package.json, go.mod, Cargo.toml, requirements.txt
• git: git log --reverse with commit history

Custom presets

Create presets.json in your project root to add or override presets:

{
  "my_game": {
    "dirs": ["game"],
    "patterns": ["*.lua"],
    "max_tokens": 8000,
    "split_mode": "by_file",
    "detect": ["game"]
  }
}

Use with: arachna --init --preset my_game

Links

• GitHub Repository
• Issue Tracker
• Changelog

License

arachna is free software licensed under GNU AGPLv3. This license guarantees the four essential freedoms: to run the program for any purpose, to study and modify it, to redistribute copies, and to distribute modified versions.

Why AGPLv3 and not MIT or Apache? Because permissive licenses allow proprietary forks. AGPLv3 ensures that derivative works — including software running as a network service — remain free. No proprietary forks. No closed modifications. What the community builds, the community keeps.

See LICENSE for the full legal text.