Getting it into your agent
One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.
npx skills add robertguss/claude-code-toolkit --skill book-market-researchgit clone --depth 1 https://github.com/robertguss/claude-code-toolkitWrote 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/robertguss/claude-code-toolkit/book-market-research)<a href="https://agentmods.dev/skills/robertguss/claude-code-toolkit/book-market-research"><img src="https://agentmods.dev/badge/skills/robertguss/claude-code-toolkit/book-market-research.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector pass
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 | $0.00083 | $0.01972 |
| Opus 5 | $0.00042 | $0.00986 |
| Sonnet 5 | $0.00017 | $0.00394 |
| Haiku 4.5 | $0.00008 | $0.00197 |
Grade A, and why
book-market-research 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 8d 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 — 248 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Market Research
Determine if a book is worth writing from a business perspective, specifically for Amazon KDP self-publishing.
Core Philosophy
Commercial viability is separate from intellectual merit. A brilliant idea can fail commercially. A mediocre idea can succeed. This skill assesses the market, not the idea itself.
Better to know the odds now. Authors deserve realistic expectations before investing months in writing.
Author intent shapes interpretation. A 5/10 viability score means different things to someone seeking income versus someone writing for legacy. Same data, different recommendations.
Claude does the analysis; human gathers the data Claude can't access. Claude performs qualitative research via web search. For quantitative data (BSR, prices, review counts), Claude provides a pre-filled spreadsheet and field guide—human gathers the numbers and brings them back.
Dependency Model
Standalone Mode: Book Concept Document only → pure commercial analysis.
Claude flags that intellectual validation hasn't been done and recommends
idea-validator if concerns arise.
Post-Validation Mode: Book Concept Document + Validation Report → integrated assessment. Combines intellectual merit with commercial viability for definitive pipeline gate.
Author Intent
Ask before researching. Author intent determines how to interpret the viability score.
| Intent | Description | Score Interpretation |
|---|---|---|
| Income | Book must generate meaningful revenue | Score is decisive—low score means revise or kill |
| Authority | Position as expert, book is a credential | Moderate score acceptable if positioning is strong |
| Passion/Legacy | "This book needs to exist" | Low score = proceed with eyes open, not a blocker |
| Lead Generation | Funnel for services/consulting | Score less critical if book serves the funnel |
| Audience Service | Serving existing followers | Platform strength matters more than market size |
What ships with it
4 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.
- 8d ago First seen · 248 lines · 83 tokens per session scan A 152a9483358f
book-market-research is a skill published in the GitHub repository robertguss/claude-code-toolkit (113 stars, last pushed 1mo ago), licensed MIT. It adds 83 tokens to every session and 1,972 once invoked, about $0.0004 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.
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