Converts a technical book (PDF or EPUB) into a structured Claude Code skill — extracting frameworks, mental models, principles, techniques, and anti-patterns the author crystallized. Use when the user wants to study a book through Claude, apply an author's frameworks while working, or build a reusable knowledge base from any PDF or EPUB.
Converts a technical book (PDF or EPUB) into a structured Claude Code skill — extracting frameworks, mental models, principles, techniques, and anti-patterns the author crystallized. Use when the user wants to study a book through Claude, apply an author's frameworks while working, or build a reusable knowledge base from any PDF or EPUB.
when_to_use
Trigger phrases — "turn this book into a skill", "create a skill from this PDF", "create a skill from this EPUB", "I want to study X book", "add this book to my skills", "convert PDF to skill", "convert EPUB to skill", "analyze this book", "extract frameworks from this book". Accepts a path to a PDF or EPUB and optional skill name slug.
Transform written knowledge into actionable Claude Code skills by extracting structure — not producing summaries.
Philosophy
Books contain crystallized expertise: frameworks, principles, and techniques that took years to develop. This skill extracts that knowledge into a format Claude can leverage repeatedly.
Extract structure, not summaries. A skill isn't a book report. It's a toolkit of:
Named frameworks (mental models with clear application)
Actionable principles (rules that guide decisions)
Techniques (step-by-step methods)
Anti-patterns (what to avoid and why)
Voice calibration (how the author thinks and communicates)
Preserve the author's precision. Frameworks often have specific names for reasons. "The 5 Whys" isn't interchangeable with "ask why multiple times." Capture the exact formulation.
Layer depth appropriately. Simple books → simple skills. Complex books with 10+ frameworks → skills with reference files and on-demand chapters.
Modes of Operation
Three paths available. Route based on what the user asks:
1. Full Conversion (Default)
Trigger: User provides a PDF path without special instructions
Action: Run all steps below (Steps 0–9)
Output: Complete skill with SKILL.md, chapters/, glossary, patterns, cheatsheet
2. Analyze Only
Trigger: User says "analyze", "just extract", or "I want to review before generating"
Action: Run Steps 0–3, then produce a structured extraction report (frameworks, principles, techniques found). Stop — do NOT generate skill files.
Output: Analysis report for user review
3. Generate from Prior Analysis
Trigger: User has existing analysis notes or previously ran analyze-only
Action: Skip Steps 0–3, use the provided analysis as input, run Steps 4–9
Output: Skill files from the provided analysis
Step 0 — Out-of-scope check
If the argument is NOT a path to a PDF or EPUB file, stop and respond:
"book-to-skill requires a PDF or EPUB path. Usage: /book-to-skill /path/to/book.pdf [skill-name] or /book-to-skill /path/to/book.epub [skill-name]"
Step 1 — Validate input
test -f "" && ||
file | grep -iE && ||
$0
echo
"FILE_OK"
echo
"FILE_NOT_FOUND: $0"
"$0"
"pdf|epub|zip"
echo
"FORMAT_OK"
echo
"FORMAT_UNKNOWN"
Check the file extension (.pdf or .epub) or magic bytes (%PDF or PK zip header).
If the file is not found or the format is not supported, stop with a clear error message listing supported formats.
Step 1.5 — Identify book type
Before extracting, ask the user:
"What kind of content does this book have? This helps me choose the best extraction method.
Text-heavy — mostly prose, few or no tables/code (e.g. management, productivity, narrative non-fiction)
Not sure — I'll use the fast method and warn you if quality seems limited"
Store the answer as BOOK_TYPE:
Option 1 → BOOK_TYPE=technical
Option 2 → BOOK_TYPE=text
Option 3 → BOOK_TYPE=text
If BOOK_TYPE=technical, inform the user before proceeding:
"📐 Technical mode selected — using Docling for structure-aware extraction (tables, code blocks, formulas preserved as markdown). This takes ~1.5s per page, so expect a few minutes for longer books. Starting now…"
If BOOK_TYPE=text, inform:
"📄 Text mode selected — using fast extraction (pdftotext). Ready in seconds."
text → prioritize "Frameworks Introduced", "Mental Models", and "Key Takeaways"; skip empty technical sections
# Chapter N: <FullTitle>## Core Idea
<1–2 sentences: the single most important thing this chapter teaches>
## Frameworks Introduced-**<FrameworkName>**: <exactformulation — preservetheauthor'snaming> - When to use: <specificsituation> - How: <stepsorcriteria>## Key Concepts-**<Term>**: <precisedefinitionin1sentence>
(5–10 most important terms from this chapter)
## Mental Models
<2–4 frameworks or thinking tools. Write as "Use X when Y" or "Think of X as Y">
## Anti-patterns-**<Whattoavoid>**: <whyitfails>## Code Examples *(technical books only — omit if BOOK_TYPE=text)*
<!-- Copy the most instructive snippet from the chapter. Preserve indentation exactly. -->
```<language>
<key code example from this chapter>
What it demonstrates:
Reference Tables (technical books only — omit if BOOK_TYPE=text)
Key Takeaways
(3–7 takeaways a practitioner must remember)
Connects To
Ch N:
:
---
## Step 8 — Generate supporting files
### glossary.md
Create `~/.claude/skills/<skill_name>/glossary.md`:
- Every significant term from the book, alphabetically sorted
- Format: `**Term** — definition (Ch N)`
- Max 1,500 tokens
### patterns.md
Create `~/.claude/skills/<skill_name>/patterns.md`:
- All concrete techniques, design patterns, algorithms from the book
- Format: `## Pattern Name\n**When to use**: ...\n**How**: ...\n**Trade-offs**: ...`
- Max 2,000 tokens
### cheatsheet.md
Create `~/.claude/skills/<skill_name>/cheatsheet.md`:
- Decision tables, comparison matrices, quick-reference rules
- The content you'd want on a single printed page
- Max 1,000 tokens
---
## Step 9 — Generate the master SKILL.md
**CRITICAL TOKEN BUDGET: Keep SKILL.md body under 4,000 tokens.**
Compaction truncates from the END — put the most important content FIRST.
Create `~/.claude/skills/<skill_name>/SKILL.md`:
```markdown
---
name: <skill_name>
description: Knowledge base from "<Full Title>" by <Author(s)>. Use when applying <author>'s frameworks for <key topics, 3–6 terms>.
when_to_use: <10–15 trigger phrases based on book topics and terms. Comma-separated.>
allowed-tools: Read Grep
argument-hint: [topic, framework name, or chapter number]
---
# <Full Title>
**Author**: <Author(s)> | **Pages**: ~<N> | **Chapters**: <N> | **Generated**: <YYYY-MM-DD>
## How to Use This Skill
- **Without arguments** — `/skill-name` loads core frameworks for reference
- **With a topic** — `/skill-name replication` → I find and read the relevant chapter
- **With chapter** — `/skill-name ch05` → I load that specific chapter
- **Browse** — ask "what chapters do you have?" to see the full index
When you ask about a topic not covered in Core Frameworks below, I will read
the relevant chapter file before answering.
---
## Core Frameworks & Mental Models
<!-- ~2,000 tokens: the author's most important named frameworks and principles.
Preserve exact names. Write as "Use X when Y", "Prefer X over Y because Z".
This is a toolkit, not a summary. -->
<generate 2,000 tokens of the most critical frameworks and insights here>
---
## Chapter Index
| # | Title | Key Frameworks |
|---|-------|----------------|
| [ch01](chapters/ch01-<slug>.md) | <Title> | <framework1>, <framework2> |
| [ch02](chapters/ch02-<slug>.md) | <Title> | <framework1>, <framework2> |
...
## Topic Index
<!-- Alphabetical. Major terms/frameworks → chapter(s) that cover them. -->
- **<Term>** → ch<N>[, ch<N>]
- **<Term>** → ch<N>
## Supporting Files
- [glossary.md](glossary.md) — all key terms with definitions
- [patterns.md](patterns.md) — all techniques and design patterns
- [cheatsheet.md](cheatsheet.md) — quick reference tables and decision guides
---
## Scope & Limits
This skill covers the book content only. For hands-on implementation in your codebase,
combine with project-specific tools. For topics beyond this book, check related skills
or ask Claude directly.
Step 10 — Cleanup and report
rm -rf /tmp/book_skill_work
Then report to the user:
✅ Skill created: ~/.claude/skills/<skill_name>/
📚 Book: <Full Title> — <Author>
📄 Pages: ~<N> | Chapters: <N>
Files generated:
SKILL.md — core frameworks + index (~X tokens)
chapters/ — <N> chapter summaries (~X tokens each, ~X total)
glossary.md — key terms (~X tokens)
patterns.md — techniques & patterns (~X tokens)
cheatsheet.md — quick reference (~X tokens)
─────────────────────────────────────────────────────
Total skill size: ~X tokens (loaded on-demand, not all at once)
💡 Tip: run /cost in Claude Code to see the actual token usage for this session.
Usage:
/<skill_name> → load core frameworks
/<skill_name> <topic> → find and explain a topic
/<skill_name> ch<N> → dive into a specific chapter
Quality Rules
Extract structure, not summaries — capture named frameworks, exact formulations, anti-patterns; not chapter recaps
Preserve the author's precision — "The 5 Whys" ≠ "ask why multiple times"; keep exact naming
Density over completeness — a 1,000-token summary beats a 10,000-token excerpt
Practitioner voice — write "Use X when Y", not "The book explains X"
Front-load SKILL.md — compaction keeps the first 5,000 tokens; most important content comes first
Chapter files are on-demand — they don't count against skill budget until loaded
Never copy raw book text — always synthesize, summarize, extract signal
Topic index is critical — it's how Claude navigates to the right chapter file
