Getting it into your agent
This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.
/plugin marketplace add melodic-software/claude-code-plugins/plugin install knowledgeWrote this? Show the measurements
A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.
[](https://agentmods.dev/skills/melodic-software/claude-code-plugins/book-distill)<a href="https://agentmods.dev/skills/melodic-software/claude-code-plugins/book-distill"><img src="https://agentmods.dev/badge/skills/melodic-software/claude-code-plugins/book-distill/github.svg" alt="Measured on agentmods" height="20"></a>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.
<a href="https://agentmods.dev/skills/melodic-software/claude-code-plugins/book-distill"><img src="https://agentmods.dev/badge/skills/melodic-software/claude-code-plugins/book-distill.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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.
| Model | Per session | Once invoked |
|---|---|---|
| Fable 5.1 | $0.00072 | $0.03888 |
| Opus 5.5 | $0.00029 | $0.01555 |
| Sonnet 5.5 | $0.00014 | $0.00778 |
| Haiku 4.5 | $0.00007 | $0.00389 |
Grade A, and why
book-distill 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 7d 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.
How it starts
The opening of the file, as written. The whole thing — 200 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Book-to-Skill Distillation
Transform technical books into structured skill reference files that provide the WHY behind decisions during development. This is a multi-session process. Each session handles ~3 chapters. The skill produces concept-organized reference files with author attribution, suitable for progressive disclosure in Claude Code skills.
Write the files into the target skill named at invocation, an existing skill to extend or a new one, at ${CLAUDE_PROJECT_DIR}/.claude/skills/<target-slug>/. Slugify the target name (lowercase alphanumerics and hyphens only; strip /, \, and ..) before building any path, and verify the resolved directory stays under ${CLAUDE_PROJECT_DIR}/.claude/skills/ before writing.
The context/ and templates/ files write the plugin data directory as <plugin-data>. Put the ${CLAUDE_PLUGIN_DATA} path this body shows in its place before a path from those files goes into a command or a file write.
- Pointer: when deciding which plugin files may carry a
${…}path and which need the placeholder, fetch https://code.claude.com/docs/en/plugins/manifest-reference#where-each-variable-resolves live. As of: 2026-10-07. Recheck trigger: that table adds supporting files to where a${…}reference resolves, or lists the Bash tool among the processes that receive the variables.
Example shape: a testing skill distilled from two books, Beck's Test-Driven Development by Example and Khorikov's Unit Testing, producing ~14 reference files, with shared files where the authors overlap.
Usage caution. Copyright
This tool is a neutral distiller: it applies a method, it does not judge what you feed it. A condensation of a copyrighted book is a derivative work (17 U.S.C. §§ 101, 106), the rights holder's exclusive rights include preparing and distributing derivatives. Keeping a private distillation for your own study is a different act from publishing, committing, or sharing one; fair use is a defense raised after the fact, not a safe harbor you can assume in advance. You own the rights decision for every book you distill and for where its outputs go. Distribute or publish a distilled output only once you have satisfied yourself that doing so is lawful for that book. This is a caution, not legal advice.
What ships with it
3 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.
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.
- 7d ago Changed · -40 tokens per session 0113b4e9e3d0
- 9d ago Changed · +4 lines f12e2565f351
- 14d ago Changed 684888581824
- 17d ago Changed · +4 lines 3ea001ca447f
- 23d ago Changed · -58 tokens per session 9e653fca0a4c
- 24d ago Changed d939b3aea252
- 1mo ago Changed 8941db5cca21
- 1mo ago First seen · 192 lines · 170 tokens per session scan A 6be701ab26be
book-distill is a skill published in the GitHub repository melodic-software/claude-code-plugins (26 stars, last pushed today), licensed MIT. It adds 72 tokens to every session and 3,888 once invoked, about $0.0003 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 2026-09-03.
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