Dewey Decimal Skill

A Claude agent to organize ebooks by the Dewey Decimal system with OCD renaming rules through three distinct Skills. Codex Skills are brand new; supporting Codex would likely require some rework. See https://developers.openai.com/codex/skills for adapting these skills to Codex's format.

skill	description
metadata-extraction	unzips .epub files and inspects metadata for author, contributors, year
filename-formatting	OCD filename rules for translators, edition, ancient authors, etc.
dewey-classification	organizes files by inferring Dewey Decimal codes from OCLC index

Setup

1. Copy config.example.ini to config.ini and edit the paths. ¹
2. Ensure your arrivals_dir and books_dir paths exist.
3. Run ./install to install the agents/skills into ~/.claude.

Usage

Run the agent:

claude --agent rename-books

For single-file processing, specify the file path. For batch processing, point it at your arrivals directory.

History File

The agent will store a history file documenting the before and after filenames, paths, and hash of each book it touches at $arrivals_dir/renames.jsonl.

Regenerating data/codes.md

If you want to rebuild the Dewey code index:

python main.py > data/codes.md

The Classification codes are indexed and cross-compared by these sources:

• lib/illinois.py - https://www.library.illinois.edu/infosci/research/guides/dewey/
• lib/oclc.py - https://www.oclc.org/content/dam/oclc/dewey/ddc23-summaries.pdf

These are orchestrated together by main.py to create data/codes.md, which is provided in this repo.

Note

DDC is proprietary and maintained by OCLC. OpenLibrary exposes dewey_decimal_class in its Books API, but coverage appears uneven; I couldn’t find a public, comprehensive ISBN↔DDC mapping. WorldCat doesn’t provide a free bulk ISBN <-> DDC mapping.

Having already learned the topology of DDC codes with respect to library shelving, categorizing by Library of Congress coding is unnatural to me, as much as I would prefer myself and all libraries to adopt it.

License

• Code - GPLv3
• Text - CC BY-SA 4.0

Footnotes

1. The [permissions] section is currently unused; agent runs appeared to ignore a local ~/.claude/settings.local.json. ↩