Create Hook Agent Skill
Create a hook (.json) to enforce policy or automate agent lifecycle events.
Install
one command, takes just this skill from the repositorynpx skills add https://github.com/microsoft/vscode --skill create-hookThe instruction itself
4 sections, as written by the authorRelated skill: agent-customization. Load and follow hooks.md for template and principles.
Guide the user to create a hook in .github/hooks/.
Extract from Conversation
First, review the conversation history. If the user has been expressing concerns about agent behavior (e.g., "don't run this command", "always check before doing X", "inject this context"), generalize that into a hook. Extract:
- Actions that should be blocked or gated
- Context that should be injected at certain points
- Automation needs at session start/end or tool use
Clarify if Needed
If no clear policy need emerges from the conversation, clarify:
- What event should trigger this hook? (e.g. PreToolUse, SessionStart, Stop)
- Should it block, warn, or inject context?
- Does it need a companion script?
Path Conventions
- Hook commands and companion scripts run with
cwddefaulting to the workspace root (when a workspace folder is available); otherwisecwdfalls back to the user home directory. Relative paths resolve fromcwd. Absolute paths are fine when intentional — just be deliberate about which you use. - Do not use environment variables for pathing. The only exception is plugin-provided environment variables in hooks shipped as part of an agent plugin; never use environment variables for pathing outside of a plugin context.
Iterate
- Draft the hook JSON (and any scripts) and save them.
- Identify the most ambiguous or weak parts and ask about those.
- Once finalized, summarize what the hook enforces, suggest ways to test it, and propose related customizations to create next.
Remember to follow the agent-customization guidelines to create highly effective hooks.
Other skills for the same job
different authors, same section of the catalogue
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Guide for creating effective skills. This skill should be used when users want to create a new skill (or update an existing skill) that extends Claude's capabilities with specialized knowledge, workflows, or tool integrations.
Guide for creating effective skills. This skill should be used when users want to create a new skill (or update an existing skill) that extends Claude's capabilities with specialized knowledge, workflows, or tool integrations.
Replace with description of the skill and when Claude should use it.
Use when facing 2+ independent tasks that can be worked on without shared state or sequential dependencies
This skill should be used when the user wants to "create a skill", "add a skill to plugin", "write a new skill", "improve skill description", "organize skill content", or needs guidance on skill structure, progressive disclosure, or skill development best practices for Claude Code plugins.
Helps users discover and install agent skills when they ask questions like "how do I do X", "find a skill for X", "is there a skill that can...", or express interest in extending capabilities. This skill should be used when the user is looking for functionality that might exist as an installable skill.
Use when creating new skills, editing existing skills, or verifying skills work before deployment
How to use it
Take microsoft/create-hook from the repository into ~/.claude/skills for personal
use, or into .claude/skills inside a project.
The agent identifies a skill by the name field in its header. Two skills with the
same name cannot sit side by side — one of them will be ignored.