Ready to supercharge your AI agents?

Install any skill in seconds. Free to start, no credit card required.

Get Started Free →

Hook Authoring Guide · majiayu000 | DecimalAI

agent toolingby majiayu000

Hook Authoring Guide

majiayu000/hook-authoring

Source majiayu000/claude-skill-registry ↗License MIT

Guide creating Claude Code hooks with security-first design.

SkillScore91Maintained

Automatic

AI Engineer packhookssdksecurity

Last verified 9/2/2026

What it changes

Passed 21 of 23 test cases with the skill, and 9 of 23 without it.

Without skill39%

With skill91%

Checks it passed that the model alone missed

The class inherits from AgentHooks.
The top-level key for the event is PostToolUse.
The class defines the async method on_pre_tool_use.

and 13 more in the full report

12 fixed9 passed either way2 still failing0 broke

Pass-rate lift: +52 pp
Tokens: +201%
Agent turns: 0%
Response time: -33%

Model gemini-3.6-flashMeasured 9/2/2026v221 of 23 cases passed with skill

Tokens, turns and time describe resource use, not a dollar price.

Use this skill

Save it into your project's skills folder. Claude Code picks it up in its next session.

curl -fsSL --create-dirs -o .claude/skills/majiayu000-hook-authoring/SKILL.md https://app.decimal.ai/s/majiayu000-hook-authoring/SKILL.md

Want it pinned and updatable? pip install "decimalai>=0.15", then decimalai skills add majiayu000-hook-authoring, and start Claude Code with claude --plugin-dir "$(git rev-parse --show-toplevel)/.agents"

1 · One-time — install the CLI (docs ↗)

pip install "decimalai>=0.15"

2 · Get the skill — writes .agents/skills/majiayu000-hook-authoring/ and pins it in .decimal/skills.lock

decimalai skills add majiayu000-hook-authoring

No CLI? Get the same file — curl · raw file

curl -fsSL --create-dirs -o .claude/skills/majiayu000-hook-authoring/SKILL.md https://app.decimal.ai/s/majiayu000-hook-authoring/SKILL.md

Raw file: /s/majiayu000-hook-authoring/SKILL.md ↗ · machine-readable summary at /s/majiayu000-hook-authoring.json ↗

Safety checks: 3 of 3 passed

Code scan CleanIntent PassedContent Clean

See it in action

One of 12 test cases the skill fixed. Same model, same prompt, with and without the skill.

1 of 12

Prompt

I am writing a PostToolUse hook script that invokes an external integration test suite. What is the maximum default execution timeout configured for hooks in Claude Code?

What was checked, without and with the skill
Checked	Without skill	With skill
The response specifies 10 minutes (or 600 seconds) as the default hook timeout.	Missed	Passed

case-12 · gemini-3.6-flash · 9/2/2026 · answers are capped and redacted

What's inside

The instructions your model reads when the skill loads.

SKILL.md587 linessingle file

Overview
Key Capabilities
Quick Start
Your First Hook (JSON - Claude Code)
Your First Hook (Python - Claude Agent SDK)
Hook Event Types
Claude Code vs SDK
JSON Hooks (Claude Code)
Python SDK Hooks
Security Essentials
Critical Security Rules
Example: Secure Logging Hook
Performance Guidelines
Performance Best Practices
Example: Efficient Hook
Scope Selection
Decision Framework
Scope Comparison
Common Patterns
Validation Hook
Logging Hook
Context Injection Hook
Testing Hooks
Unit Testing
Module References
Tools
Related Skills
Next Steps
References

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.

Track record

Benchmark

21 / 23

test cases passed, vs 9 / 23 without

Adoption

Users: 0
Times used: 0

Safety and source details

SkillSafety

✓ 3 of 3 passed

Code scan14 of 15 checks clean

0 critical · 0 warning · 4 info — scanner v4 — 8/10/2026

View 15 scanner checks

live_secretremote_code_executionreverse_shelldata_exfiltrationssrf_metadataagent_snoopinganti_refusaldestructive_commandsobfuscated_unicodeunicode_homoglyphopaque_blobsuspicious_urltool_overreachtrigger_abuseprompt_injection_phrasing

No issues (informational notes only).

IntentSafe

LLM judge · does the skill do what it claims

ContentClean

LLM judge · policy & harmful-content review

Source

Imported

majiayu000 / claude-skill-registry

skills/agent/hook-authoring-athola-claude-night-market-2/SKILL.md

View on GitHub ↗

License MITImported 8/10/2026Version v2

Other skills for the same job

Published skills whose descriptions closely match this one, with their headline benchmark lift.

More skills from the same source and nearby in the registry, with their headline benchmark lift.

Ready to supercharge your AI agents?

See it in action

What's inside

Table of Contents

Hook Authoring Guide

Overview

Track record

Benchmark

Adoption

SkillSafety

Source

Other skills for the same job

Related skills