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 agentmods add skills/andisab/swe-marketplace/hook-devnpx skills add andisab/swe-marketplace --skill hook-devgit clone --depth 1 https://github.com/andisab/swe-marketplaceWrote 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/andisab/swe-marketplace/hook-dev)<a href="https://agentmods.dev/skills/andisab/swe-marketplace/hook-dev"><img src="https://agentmods.dev/badge/skills/andisab/swe-marketplace/hook-dev.svg" alt="Measured on agentmods" 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 | $0.00080 | $0.04718 |
| Opus 5 | $0.00040 | $0.02359 |
| Sonnet 5 | $0.00016 | $0.00944 |
| Haiku 4.5 | $0.00008 | $0.00472 |
Grade C, and why
hook-dev scanned grade C with 3 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 6d 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.
Sends data to an external URLmediumData exfiltration
A POST to an outside endpoint may be telemetry or may be exfiltration; either way the mod talks to somewhere, and you should know where.
"command": "jq '.' | curl -d @- https://external-log-service.com" Reads agent configuration directoriesmediumAgent snooping
.claude/, .codex/, .gemini/ hold keys, settings and other credentials a mod has no legitimate need for.
- **User-level**: `~/.claude/settings.json` (all projects) Makes network callslowCapability
Not a fault in itself. Listed so you know the mod talks to something, and to what.
"command": "jq '.' | curl -d @- https://external-log-service.com" How it starts
The opening of the file, as written. The whole thing — 792 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Hook Dev Skill
This skill helps create production-ready Claude Code hooks following Anthropic's official specifications.
What are Hooks?
Hooks are user-defined shell commands that execute at various points in Claude Code's lifecycle. They provide:
- Deterministic control: Ensure actions happen automatically, not relying on LLM decisions
- Workflow automation: Format code, run linters, log commands
- Custom notifications: Alert when Claude needs input
- Permission systems: Block sensitive file modifications
- Feedback loops: Validate code changes against conventions
Hook vs Skill vs Command
| Feature | Hook | Skill | Command |
|---|---|---|---|
| Trigger | Lifecycle event | Context match | User invocation |
| Type | Shell command | AI capability | Prompt template |
| Use case | Automation, validation | Autonomous features | Reusable prompts |
| Control | Deterministic | LLM-driven | User-initiated |
When to use Hooks: Automatic formatting, logging, notifications, permission control, code validation
Hook Events
Ten lifecycle events trigger hooks:
1. PreToolUse
Executes after Claude creates tool parameters but before processing.
Use cases:
- Block edits to sensitive files (.env, production configs)
- Validate bash commands before execution
- Request confirmation for destructive operations
- Log all tool usage for auditing
- Modify tool inputs programmatically
Blocking capability: Yes - exit code 2 blocks with error fed to Claude; JSON output with "permissionDecision": "deny" also blocks
2. PostToolUse
Runs immediately after successful tool completion.
Use cases:
- Format code after edits (Prettier, Black, gofmt)
- Run linters after file modifications
- Sync changes to external systems
- Update indexes or caches
Blocking capability: No - tool already executed
3. UserPromptSubmit
Fires when users submit prompts, before Claude processes them.
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.
- 6d ago First seen · 792 lines · 80 tokens per session scan C c5b6de793edf
hook-dev is a skill published in the GitHub repository andisab/swe-marketplace (21 stars, last pushed 17d ago), licensed MIT. It adds 80 tokens to every session and 4,718 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it C with 3 findings (sends data to an external url, reads agent configuration directories, makes network calls). No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.
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pr
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new
Use when user asks to create a release, cut a release, or publish a version. Auto-detects GitHub vs GitLab vs Gitea, calculates semantic version, generates release notes from PRs/MRs or commits, shows preview for confirmation before publishing.
writing-style
Use for technical communication - GitHub/GitLab tickets, PR/MR descriptions, issue comments, code review comments, commit messages. Direct, brief style with no AI-speak. NOT for README.md, public docs, or blog posts.
root-cause-investigator
Systematic root cause analysis for errors, bugs, and unexpected behaviors using 5-Why methodology. Use when user reports errors, build failures, test failures, performance issues, integration problems, or any "it's not working" scenarios.
ccc-console
The Commander Console: one inline panel — agents, usage, safety, memory, history — plus a prompt bar that reaches this session. Publishing a snapshot is separate and consent-gated.
ccc-browse
Visual, filterable catalog of every CC Commander skill, agent, and command. Cascades from broad category picker into 4-at-a-time detail cards. Use when the user types…