Book-to-skill turns technical books, document folders, or source collections into structured skills that agents can consult on demand. Developers use it to preserve practical knowledge such as frameworks, decision rules, and chapter-specific material for later work. The catalogue includes instructions and a skill for using this workflow with coding agents.
Borrowing it
Nothing to install: this file belongs to virgiliojr94/book-to-skill. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.
curl -O https://raw.githubusercontent.com/virgiliojr94/book-to-skill/master/AGENTS.mdgit clone --depth 1 https://github.com/virgiliojr94/book-to-skillWrote 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/instructions/virgiliojr94/book-to-skill/agents-md)<a href="https://agentmods.dev/instructions/virgiliojr94/book-to-skill/agents-md"><img src="https://agentmods.dev/badge/instructions/virgiliojr94/book-to-skill/agents-md/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/instructions/virgiliojr94/book-to-skill/agents-md"><img src="https://agentmods.dev/badge/instructions/virgiliojr94/book-to-skill/agents-md.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 | $0.01069 | $0.01069 |
| Opus 5 | $0.00535 | $0.00535 |
| Sonnet 5 | $0.00214 | $0.00214 |
| Haiku 4.5 | $0.00107 | $0.00107 |
Grade A, and why
book-to-skill AGENTS.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 11d 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 — 109 lines — stays where its author put it; the contents beside it link to each section on GitHub.
AGENTS.md
This file is the repository-wide execution contract for coding agents.
Project intent
book-to-skill converts books and documents into structured, on-demand Agent Skills. The repository has two distinct halves:
- a deterministic Python extractor (
scripts/extract.py->book_to_skill/), and - a spec-driven generator (
SKILL.md) executed by an agent.
Do not blur those responsibilities without a measured reason.
Sources of truth
Before changing code, read the smallest relevant set of files:
CONTRIBUTING.md— contribution rules and required checks.docs/architecture.md— current architecture and component ownership.SKILL.md— only when generation behavior or generated-skill structure is in scope.SECURITY.mdandSECURITY-NOTICE.md— when touching parsing, files, subprocesses, generated content, or dependencies.- Existing tests closest to the code being changed.
For the progressive-disclosure research/evaluation initiative, also read:
docs/research/progressive-disclosure-evals.md
That document is the execution ledger and defines task order, evidence gates, and which paper-derived ideas are hypotheses rather than product requirements.
Non-negotiable rules
- Measure, do not assert. No claimed quality, token, routing, accuracy, or cost improvement without reproducible evidence.
- Do not turn a paper hypothesis into production behavior before its gate passes. In particular, do not add KEY_ELEMENTS-style metadata, library mode, deeper routing, or new
SKILL.mdcontent merely because it sounds plausible. - Keep
SKILL.mdlean. It is always-loaded converter context. Any net growth needs evidence that the added context earns its cost. - Never commit raw copyrighted book text. Use synthetic, public-domain, or explicitly licensed fixtures. Keep private evaluation corpora and raw live trajectories out of git.
- Avoid new runtime dependencies for evaluation work. Evaluation-only dependencies belong outside the core runtime and must be justified.
- Do not edit
CHANGELOG.mdby hand. - Preserve backwards compatibility unless the task explicitly authorizes a breaking change.
- Do not weaken security checks, path hardening, sanitization, or generated-skill scanning to make an experiment pass.
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.
- 11d ago First seen · 109 lines · 1,069 tokens per session scan A 6be2195c4ff0
book-to-skill AGENTS.md is an instructions file published in the GitHub repository virgiliojr94/book-to-skill (29,614 stars, last pushed 4d ago), licensed MIT. It adds 1,069 tokens to every session, about $0.0053 per session on Opus 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 2026-08-30.
Other instructions, from other repositories
next.js AGENTS.md
AGENTS.md instructions for vercel/next.js, covering next.js development guide, codebase structure, monorepo overview, core package: packages/next and other important packages.
codex AGENTS.md
AGENTS.md instructions for openai/codex, covering rust/codex-rs, the codex-core crate, code review rules, crate api surface and model visible context.
vscode buildNext.instructions.md
Working notes and architecture documentation for the new esbuild-based build system in build/next. Use when making changes to the new build pipeline (transpile/bundle commands, NLS plugin, source-map handling, resource copying, or self-hosting watch tasks).
spec-kit AGENTS.md
AGENTS.md instructions for github/spec-kit, covering agents.md, about spec kit and specify, quickstart — add a new integration in 5 steps, integration architecture and integrationmanifest — file tracking.
vscode oss-third-party-notices.instructions.md
Instructions for microsoft/vscode, covering vs code oss third-party-notices pipeline, architecture, pipeline flow in ci, applying the notice (cutover) and fallback chain (never fail the build).
langchain AGENTS.md
AGENTS.md instructions for langchain-ai/langchain, covering global development guidelines for the langchain monorepo, corridor security analysis, project architecture and context, monorepo structure and development tools & commands.