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 troykelly/claude-skills --skill hook-developmentgit clone --depth 1 https://github.com/troykelly/claude-skillsWrote 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/troykelly/claude-skills/hook-development)<a href="https://agentmods.dev/skills/troykelly/claude-skills/hook-development"><img src="https://agentmods.dev/badge/skills/troykelly/claude-skills/hook-development/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/troykelly/claude-skills/hook-development"><img src="https://agentmods.dev/badge/skills/troykelly/claude-skills/hook-development.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 | $0.00117 | $0.04027 |
| Opus 5.5 | $0.00047 | $0.01611 |
| Sonnet 5.5 | $0.00023 | $0.00805 |
| Haiku 4.5 | $0.00012 | $0.00403 |
Grade A, and why
Hook Development 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 1mo 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.
The source is not reproduced here
No licence file
A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.
What ships with it
10 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.
- examples/load-context.sh 1.7 KB runs code
- examples/validate-bash.sh 1.3 KB runs code
- examples/validate-write.sh 1.2 KB runs code
- references/advanced.md 9.9 KB
- references/migration.md 8.1 KB
- references/patterns.md 7.0 KB
- scripts/hook-linter.sh 4.1 KB runs code
- scripts/README.md 3.6 KB
- scripts/test-hook.sh 5.2 KB runs code
- scripts/validate-hook-schema.sh 5.0 KB runs code
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.
- 1mo ago First seen · 718 lines · 117 tokens per session scan A 47b6afd3f0bf
Hook Development is a skill published in the GitHub repository troykelly/claude-skills (11 stars, last pushed 9mo ago), with no licence file. It adds 117 tokens to every session and 4,027 once invoked, about $0.0005 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 2026-08-30.
Other skills, from other repositories
skill-creator
Create a skill or bring an existing one up to the same standard (validate + asm eval fix loop); run evals, tune triggering. Use when authoring, fixing, or retrofitting a skill. Don't use for invoking skills, writing prose, or Python scaffolds.
find-me-skills
Find Agent Skills for a goal the user cannot name yet, then export an installable bundle. Use when they ask which skills fit a project. Don't use for installing named skills, authoring skills, or catalog maintenance.
skill-upstream-pr
Improve an open-source GitHub skill and open a friendly suggestion PR upstream: fork, run skill-creator's retrofit, attach asm eval before/after metrics. Don't use for local-only skills, authoring from scratch, bulk repos, or registry publish.
skill-index-updater
Add GitHub skill repos to the ASM index: clone, audit, eval, regenerate index, rebuild catalog, open PR. Use when given GitHub URLs to onboard. Don't use for refreshing indexed repos (refresh-index), improving skills (skill-creator), or install.
hello-world
A minimal test skill that greets the user and demonstrates the ASM publish workflow.
audit-pr
Audit a whole PR against the delivery contract and return MERGE-READY or evidenced blockers with the full URL. Consumes the current review-change REVIEW-PASS receipt instead of re-running review axes; posts a SHA-bound ready comment; never edits or merges. Triggers: "audit-pr", "is this PR ready", "merge gate".