hook-authoring SKILL.md skillA
hook-authoring from athola/claude-night-market is an agent skill: a SKILL.md folder an AI agent loads when a task calls for it.
mdr add athola/claude-night-market/hook-authoring@git:20261014.2769a9cPins git:20261014.2769a9c in mdr.lock. Pin the fingerprint instead.
- Audit grade
- A, 17 of 17 checks passed
- Kind
- SKILL.md skill
- Repository
- athola/claude-night-market
- Path
plugins/abstract/skills/hook-authoring/SKILL.md- Versions recorded
- 8
- Latest version
- git:20261014.2769a9c, committed Oct 14, 2026
- First version recorded
- Jun 28, 2026
- Size
- 17,569 bytes
- Repository stars
- 348
- License
- MIT
Guide creating Claude Code hooks with security-first design. Use for validation and enforcement.
Collected from public GitHub. Every version is saved exactly as it was and never changes. Install it at an exact version with the mdr tool, and every file is checked before it reaches your agent. The main file is checked against the SHA-256 fingerprint recorded here, and the others against the fingerprints GitHub keeps for its source commit. The automatic checks below grade the latest version, and the same checks always give the same file the same grade.
What the file says
## When NOT To Use - Auditing a hook that already exists (use `abstract:hooks-eval`) - Choosing where a hook should live (use `abstract:hook-scope-guide`) - Authoring a skill rather than a hook (use `abstract:skill-authoring`) # Hook Authoring Guide ## Overview Hooks are event interceptors that allow you to extend Claude Code and Claude Agent SDK behavior by executing custom logic at specific points in the agent lifecycle. They enable validation before tool use, logging after actions, context injection, workflow automation, and security enforcement. This skill teaches you how to write effective, secure, and performant hooks for both declarative JSON (Claude Code) and programmatic Python (Claude Agent SDK) use cases. ### Key Capabilities - **PreToolUse**: Validate, filter, or transform tool inputs before execution; inject context (2.1.9+) - **PostToolUse**: Log, analyze, or modify tool outputs after execution - **UserPromptSubmit**: Inject context or filter user messages before processing - **Stop/SubagentStop**: Cleanup, final reporting, or result aggregation - **TeammateIdle/TaskCompleted**: Multi-agent coordination and orchestration (2.1.33+) …
Read the whole file at its exact version.
How to install
mdr add athola/claude-night-market/hook-authoring@sha256:de48751b016a7b04The line at the top of this page pins the label git:20261014.2769a9c, which is what most people want. This one pins the sha256 fingerprint of the contents instead, so it survives a label being moved. Either way the exact version is written to mdr.lock, and mdr install downloads and checks those contents again, so it installs them exactly or stops with an error.
[](https://markdownregistry.com/a/art_4invrye5xabuw4oy)
5 badge image fetches in 30 days. What the badge shows.
Versions
The registry has recorded 8 versions of this file, between Jun 28, 2026 and Oct 14, 2026, about one every 16 days.
| version | committed | commit | size | audit | |
|---|---|---|---|---|---|
| git:20261014.2769a9c latest | 2026-10-14 | 2769a9c | 17,569 B | A | view · diff |
| git:20261005.3797ed5 | 2026-10-05 | 3797ed5 | 17,797 B | A | view · diff |
| git:20261005.ff6bcd9 | 2026-10-05 | ff6bcd9 | 24,883 B | A | view · diff |
| git:20260902.4a35d69 | 2026-09-02 | 4a35d69 | 24,260 B | A | view · diff |
| git:20260818.c9da32c | 2026-08-18 | c9da32c | 25,550 B | A | view · diff |
| git:20260813.0bee82e | 2026-08-13 | 0bee82e | 25,514 B | A | view · diff |
| git:20260713.f98719b | 2026-07-13 | f98719b | 25,390 B | A | view · diff |
| git:20260628.2324895 | 2026-06-28 | 2324895 | 25,160 B | A | view |
Audit of the latest version
- pass: Frontmatter block present
- pass: Frontmatter declares a name
- pass: Frontmatter declares a description
- pass: Size between 200 bytes and 200 KB (17569 bytes)
- pass: No zero-width or bidi control characters
- pass: No instruction hidden inside an HTML comment
- pass: No link to an exfiltration or paste host
- pass: No credential-shaped string
- pass: No instruction to send local credentials anywhere
- pass: No text hidden with inline styles
- pass: No prompt-injection phrasing
- pass: No curl or wget piped into a shell
- pass: No recursive delete of root, home or parent
- pass: No instruction to read or print local credentials
- pass: No base64 blob over 200 characters
- pass: No link to a raw IP address
- pass: No script tag
Source
athola/claude-night-market · 348 stars · license MIT · pushed 2026-11-05 · branch master
API
GET https://markdownregistry.com/api/v1/artifacts/art_4invrye5xabuw4oy GET https://markdownregistry.com/api/v1/resolve?ref=athola/claude-night-market/hook-authoring GET https://markdownregistry.com/api/v1/blob/de48751b016a7b0403d383850bf32c499ee4373996c9f0cb53f2fe7aaf161b6a
Your AI assistant does the legwork. You hear about the deals worth your word. Hand yours the standing instructions at modelranch.com and it joins the network that reads files like this one.
Guides: the SKILL.md format and its required fields · what to check before you install a skill · how to pin a skill to an exact version · where to find agent skills · keeping a team on the same skills · which agent file does what.