Getting it into your agent
It runs from inside its repository, so the clone comes first — what it calls does not travel with the file alone.
git clone --depth 1 https://github.com/athola/claude-night-marketnpx agentmods add skills/athola/claude-night-market/rule-catalogWrote 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/athola/claude-night-market/rule-catalog)<a href="https://agentmods.dev/skills/athola/claude-night-market/rule-catalog"><img src="https://agentmods.dev/badge/skills/athola/claude-night-market/rule-catalog/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/athola/claude-night-market/rule-catalog"><img src="https://agentmods.dev/badge/skills/athola/claude-night-market/rule-catalog.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Rogue Agent · line 204 Skill modifies its own code, configuration, or behavior at runtime. Self-modification enables an agent to escalate privileges, disable safety constraints, or install persistent backdoors.Fix: Prevent the skill from modifying its own code, SKILL.md, or configuration files. Treat skill files as read-only at runtime.
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 | $0.00036 | $0.01765 |
| Opus 5 | $0.00018 | $0.00882 |
| Sonnet 5 | $0.00007 | $0.00353 |
| Haiku 4.5 | $0.00004 | $0.00177 |
Grade A, and why
rule-catalog 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 — 225 lines — stays where its author put it; the contents beside it link to each section on GitHub.
When To Use
- Browsing available hookify rules by category
- Installing standard pre-built rules into a project
- Looking for ready-made rules before writing custom ones
When NOT To Use
- Writing custom rules from scratch: use
hookify:writing-rulesinstead - Debugging or modifying existing installed rules
- Converting Python SDK hooks: use
hookify:from-hookinstead
Table of Contents
- Quick Install
- Available Rules
- git/ - Git Safety
- python/ - Python Quality
- security/ - Security Gates
- workflow/ - Workflow Enforcement
- performance/ - Resource Management
- Installation Instructions
- Method 1: Claude-Assisted (Recommended)
- Method 2: Python Script
- Method 3: Manual Copy
- Rule File Locations
- Customizing Rules
- Creating Pull Requests for New Rules
- Related
Hookify Rule Catalog
Pre-built rules for common scenarios. Install directly or use as templates.
Quick Install
# Install a specific rule
Skill(hookify:rule-catalog) then install git:block-force-push
# Or use the Python installer for bulk operations
python3 plugins/hookify/scripts/install_rule.py git:block-force-push
python3 plugins/hookify/scripts/install_rule.py --category git
python3 plugins/hookify/scripts/install_rule.py --all
Verification: Run python --version to verify Python environment.
Available Rules
git/ - Git Safety
| Rule | Action | Default | Description |
|---|---|---|---|
block-force-push |
block | enabled | Prevent force push to main/master |
block-destructive-git |
block | enabled | Block reset --hard, checkout -- ., clean -fd, etc. |
warn-risky-git |
warn | enabled | Warn about rebase -i, soft reset, etc. |
warn-large-commits |
warn | enabled | Warn about large binary files |
What ships with it
14 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.
- rules/documentation/require-slop-scan-for-docs.md 2.4 KB
- rules/git/block-destructive-git.md 3.7 KB
- rules/git/block-force-push.md 1.0 KB
- rules/git/warn-large-commits.md 751 B
- rules/git/warn-risky-git.md 1.3 KB
- rules/performance/warn-large-file-ops.md 1009 B
- rules/python/block-dynamic-code.md 1.3 KB
- rules/python/warn-print-statements.md 1.2 KB
- rules/security/destructive-command-guard.md 2.6 KB
- rules/security/require-security-review.md 1.2 KB
- rules/stewardship/campsite-check.md 909 B
- rules/workflow/enforce-scope-guard.md 923 B
- rules/workflow/plan-before-large-dispatch.md 2.4 KB
- rules/workflow/require-spec-before-code.md 1.0 KB
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 · 225 lines · 36 tokens per session scan A 4d27f50df448
rule-catalog is a skill published in the GitHub repository athola/claude-night-market (337 stars, last pushed yesterday), licensed MIT. It adds 36 tokens to every session and 1,765 once invoked, about $0.0002 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 2026-09-03.
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