Data & Analysis

Public-Domain Mystery Books: 50 With Checked Links

Data catalog, not an instruction skill: 50 crime and detective books from Project Gutenberg, each with title, author, Gutenberg number, download count and an EPUB address that answered on 2026-10-28. Rights are the United States only. Use when an agent needs public domain detective books, free mystery ebooks or classic crime novels with links already checked.

Public-Domain Mystery Books: 50 With Checked Links is a tested SKILL.md that data catalog, not an instruction skill: 50 crime and detective books from Project Gutenberg, each with title, author, Gutenberg number, download count and an EPUB address that answered on 2026-10-28; an agent buys it once for $0.10 over x402.

Tested 2026-10-28No code, no hidden instructionsv1.0.0 · 10.7 KB · perpetual license

Not for

Book texts: this file lists addresses, it does not contain a single chapter. Not a legal opinion: rights are the United States only, and another country may protect the same work. Not a recommendation list, since rank is downloads. No audio books, no paper editions, no books after about 1930.

Tested, honestly

Tested 2026-10-28 with a strong and a weak model.

SonnetStrong model, claude-sonnet-5-5
Answered all 10 questions about the detective and crime books list correctly from the file: the first title, a mid-list Gutenberg number, the exact addresses of the last and a middle book, the download count of number five and the first three titles of the busiest author. Asked for a book that belongs to another genre it said the book is not in this catalog and gave no address; asked about Germany it named the United States limit of the rights. One answer first scored as a miss only because it swapped a long dash in a title for a comma; the check was loosened and the recorded answers were rescored, no new run.
HaikuWeak model, claude-haiku-5-5
Also answered all 10 questions, with shorter replies. It copied the EPUB addresses exactly, returned the right counts and the check date, and refused to give an address for a book that is not in the file. The rights question got a shorter reply than Sonnet's, but it still named the United States.

Full test summary

Example

Our own test text, before and after the skill ran. Excerpts only.

English · claude-sonnet-5-5

Before

Which book is number 1 in the catalog?

After

Number 1 in the catalog is **The Adventures of Sherlock Holmes** by Arthur Conan Doyle (Gutenberg #1661, 96,353 downloads). EPUB: https://www.gutenberg.org/ebooks/1661.epub3.images The link answered with an EPUB file when checked on 2026-10-28. Rights are public domain in the United States only.

What is in the file

  • What was checked
  • Rules for the agent that reads this file
  • The 50 books

Languages

English. Tried in: English.

License

Perpetual, non-exclusive; use and modify for yourself incl. paid work; no resale or republishing. Holder: Georgi Kalchev, aiskills402.com. Full terms.

Versions

Current version 1.0.0, updated 2026-10-28. Whoever bought an earlier version gets new ones free through the same re-download token.

  1. v1.0.0 · 2026-10-28

    First release: 50 crime and detective books with title, author, Gutenberg number, download count and EPUB address. All 50 addresses answered with an EPUB archive on 2026-10-28. Rights are the United States only. Rank is the download count of Project Gutenberg's public API read on 27 and 28 October 2026. Price: $0.10; the value is the checking and the ordering, not the books.

FAQ

Which detective stories lead the list?

The Adventures of Sherlock Holmes, Dracula, The strange case of Dr. Jekyll and Mr. Hyde. Rank follows the download count kept by Project Gutenberg's public API, read on 27 and 28 October 2026, so it changes slowly but does change.

Can a shop sell these crime novels as paid ebooks?

This file does not answer that. It records only that Project Gutenberg marks each work as out of copyright for US readers, and that the gutenberg.org address returned an EPUB. Selling is your own legal question, and so is any other country.

How many mystery entries had a dead address?

None. All 50 entries answered with a zip-based EPUB archive on 2026-10-28. The check requests only the first kilobyte of each file, so it proves the address is alive, not that every chapter is intact.

Does the detective list say which novel to read first?

It does not. A reader who wants a starting point among series characters must look elsewhere; the file only orders by downloads and never judges plot, period or difficulty. Series order, spoilers and the quality of a translation are equally outside it.

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Read this page as Markdown: /skills/public-domain-books-mystery.md.

  • Public-Domain Romance Books: 50 With Checked Links

    Data & Analysis

    SKILL.md · v1.0.0 · 10.6 KB

    Data catalog, not an instruction skill: 50 romance novels from Project Gutenberg, each with title, author, Gutenberg number, download count and an EPUB address that answered on 2026-10-28. Rights are the United States only. Use when an agent needs public domain romance books, free romance ebooks or classic love stories with links already checked.

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  • Public-Domain Science Fiction Books: 50 With Checked Links

    Data & Analysis

    SKILL.md · v1.0.0 · 10.6 KB

    Data catalog, not an instruction skill: 50 science fiction books from Project Gutenberg, each with title, author, Gutenberg number, download count and an EPUB address that answered on 2026-10-28. Rights are the United States only. Use when an agent needs public domain science fiction, free sci-fi ebooks or classic space adventure books with links already checked.

    $0.10once

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    • Base
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    Tested with Sonnet and Haiku, 28 Oct 2026

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