writing-hooks
Writing Hooks
Scope: covers hooks.json authoring and hook script design. For plugin architecture, see [[writing-plugins]]. For rules (which are simpler but static), see [[writing-rules]].
1. Three Hook Types
| Type | What it does | When to use | Complexity |
|---|---|---|---|
command |
Runs a shell script, reads JSON from stdin | Deterministic checks: file existence, JSON validation, regex matching | Medium |
prompt |
Injects text into Claude's context | Advisory: reminders, context injection, style guidance | Low |
agent |
Spawns a verification agent | Complex verification: code quality, semantic analysis, multi-file checks | High |
Type Selection Flowchart
Is the check deterministic (regex, file exists, JSON schema)?
YES --> command hook (shell script)
NO --> Does it need AI judgment?
YES --> agent hook
More from xiaolai/nlpm-for-claude
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Use when writing or reviewing NL artifacts and need to check for anti-patterns — vague quantifiers, prohibitions without alternatives, oversized skills, write-on-read-only agents, monolithic prompts, or linter-duplicating rules.
2conventions
Use when writing, reviewing, or validating Claude Code plugin artifacts — check frontmatter schemas, hook event names, naming conventions, prompt structure, or reference syntax. Loaded by the NLPM scorer and checker agents for schema validation.
2writing-prompts
How to write effective system prompts for any LLM. Universal prompt engineering -- role clarity, structured output, injection resistance, few-shot examples. Use when writing prompts, system instructions, or AI configuration.
2scoring
Use when scoring NL artifact quality, applying penalties, or calibrating lint judgment — contains the 100-point rubric with penalty tables per artifact type and 4 worked calibration examples.
1security
Detects execution surface risks, supply chain vulnerabilities, data exfiltration vectors, and prompt injection patterns in Claude Code plugins. Use when auditing plugins for security risks, reviewing MCP server configurations, scanning hooks and scripts for vulnerabilities, or checking extensions before installation.
1testing
Use when writing test specs for NL artifacts, running /nlpm:test, or setting up TDD workflows for skills, agents, commands, rules, hooks, and prompts.
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