shuck-file: Instructions file for Claude Code

CLAUDE.md

shuck-file CLAUDE.md is an instructions file for Claude Code from Shan-Zhu/shuck-file. It costs 990 tokens per session, scanned A, original, MIT.

Development instructions for shuck-file, a document-to-Markdown converter for AI agents. It chooses between direct output and a document map with extraction options based on file size.

In plain words
What is it for?
Use it to convert documents for an AI agent, inspect selected sections, search within a file, or run the project’s tests and MCP server.
Why use it?
They show how to install, test and run the converter, including targeted extraction from large documents.

Instructions file for Claude Code

Written for Claude Code: the file is CLAUDE.md. Also seen: mentions .claude-plugin; mentions CLAUDE.md; mentions Claude Code.

This is Shan-Zhu/shuck-file's own configuration. It tells Claude Code how to work on shuck-file itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything shuck-file configures →

Reuse

Borrowing it

Nothing to install: this file belongs to Shan-Zhu/shuck-file. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/Shan-Zhu/shuck-file/master/CLAUDE.md
Clone the repo
git clone --depth 1 https://github.com/Shan-Zhu/shuck-file

Made for: Claude Code.

Wrote this? Show the measurements

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README.md
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Your own site
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Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

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Per session 990 This file is loaded in full into every session.
When invoked 990 The same file — it is already loaded in full.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00990 $0.00990
Opus 5.5 $0.00396 $0.00396
Sonnet 5.5 $0.00198 $0.00198
Haiku 4.5 $0.00099 $0.00099

Measured 2mo ago against content hash 17edb6e4eacd, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

shuck-file CLAUDE.md scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 2mo ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

CLAUDE.md · 101 lines

How it starts

The opening of the file, as written. The whole thing — 101 lines — stays where its author put it; the contents beside it link to each section on GitHub.

CLAUDE.md

This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.

Commands

# Install in development mode
pip install -e .

# Run all tests
python -m pytest tests/ -v

# Run a single test file
python -m pytest tests/test_router.py -v

# Run a single test
python -m pytest tests/test_router.py::TestRouterAutoRouting::test_small_file_direct -v

# CLI usage (after pip install -e .)
shuck <file>
shuck probe <file>              # force map mode
shuck <file> --all              # force full output
shuck <file> --grep "keyword"
shuck <file> --sections s1,s3
shuck <file> --budget 4000

# CLI usage (without install, from repo root)
python plugin/shuck.py <file>

# MCP Server development
fastmcp dev src/shuck_file/server.py

Architecture

shuck-file is a document-to-Markdown converter for AI agents. Its core design: one command, smart behavior — small files output directly, large files return a document map with extraction options.

Package Structure

src/shuck_file/              # PyPI package (the source of truth)
  ├── __init__.py             # Version
  ├── cli.py                  # CLI entry point (console_scripts: shuck)
  ├── server.py               # MCP Server (FastMCP)
  ├── core/                   # Core logic
  │   ├── router.py           # Auto-routing
  │   ├── segmenter.py        # Document segmentation
  │   ├── mapper.py           # Map mode renderer
  │   ├── budget.py           # Smart compression
  │   ├── grep.py             # In-document search
  │   ├── frontmatter.py      # YAML frontmatter
  │   └── models.py           # Data models
  └── extractors/             # Format-specific extractors
      ├── base.py             # Base extractor ABC
      ├── docx_ext.py         # Word
      ├── pdf_ext.py          # PDF
      ├── xlsx_ext.py         # Excel
      ├── pptx_ext.py         # PowerPoint
      └── csv_ext.py          # CSV

plugin/                       # Claude Code plugin (thin wrapper)
  ├── shuck.py                # Delegates to shuck_file.cli.main()
  ├── .claude-plugin/         # Plugin manifest
  └── commands/               # Skill definitions

Read the full file on GitHub · 101 lines

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 2mo ago First seen · 101 lines · 990 tokens per session scan A 17edb6e4eacd

Subscribe to this mod's changes

shuck-file CLAUDE.md is an instructions file published in the GitHub repository Shan-Zhu/shuck-file (6 stars, last pushed 7mo ago), licensed MIT. It adds 990 tokens to every session, about $0.0040 per session on Opus 5.5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-31.

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