How do I install the Claude Codehook skill?

Run npx skillmds@latest add tomevault-io/claude-codehook in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Claude Codehook safe to use?

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Which AI agents work with Claude Codehook?

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Is Claude Codehook free to use?

Yes. Installing skills from SkillMD is free, and the skill stays under its author's original license.

Who published Claude Codehook?

tomevault-io (@tomevault-io) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Claude Codehook by tomevault-io — Agent Skill

Name: Claude Codehook
Author: tomevault-io

Claude Codehook

Use this skill when you need to configure, create, or troubleshoot Claude Code hooks. This includes setting up PreToolUse hooks, PostToolUse hooks, UserPromptSubmit hooks, debugging hook failures, or any automation within Claude Code. Examples include "I want to run tests before every file edit", "My hook isn't firing", "1 out of 2 hooks ran", or "How do I create a hook that formats JSON output with jq?

tomevault-io Updated Sep 17, 2026

File contents

Claude Code Hooks

Reference for creating and configuring Claude Code hooks. When uncertain about syntax or features, use the Task tool with subagent_type='claude-code-guide' to consult official documentation.

Hook Types

Type	Trigger	Use Cases
PreToolUse	Before tool execution	Validate inputs, block operations, modify parameters
PostToolUse	After tool completes	Check results, run linters, provide feedback
UserPromptSubmit	When user sends message	Pre-process input, add context
Stop	Session ends	Cleanup, save state
SubagentStop	Subagent completes	Process results
PreCompact	Before context compaction	Save important state
Notification	System notification	Log events

Configuration Files

~/.claude/settings.json - User-level (global)
.claude/settings.json - Project-level
.claude/settings.local.json - Local (not committed)
Plugin hooks: plugins/<name>/hooks/hooks.json

Hook Structure

{
  "hooks": {
    "PostToolUse": [
      {
        "matcher": "Edit|Write",
        "hooks": [
          {
            "type": "command",
            "command": "bun ./hooks/biome"
          }
        ]
      }
    ]
  }
}

Matcher Patterns:

Simple: "Write", "Edit"
Multiple: "Edit|Write|MultiEdit"
With args: "Bash(npm:*)", "Bash(osascript:*)|Bash(open:*)"
MCP tools: "mcp__linear__create_issue"
Plugin MCP tools: "mcp__plugin_<plugin>_<namespace>__<tool>"
Claude AI MCP tools: "mcp__claude_ai_<DisplayName>__<tool>"
All three patterns: "mcp__linear__create_issue|mcp__plugin_linear_linear__create_issue|mcp__claude_ai_Linear__save_issue"

Hook Input

Commands receive JSON on stdin:

{
  "tool_name": "Write",
  "tool_input": {
    "file_path": "/path/to/file.ts",
    "content": "..."
  },
  "cwd": "/project/root",
  "session_id": "...",
  "transcript_path": "..."
}

Parse in shell:

input=$(cat)
file_path=$(echo "$input" | jq -r '.tool_input.file_path')

Or use @constellos/claude-code-kit/runners:

import { readStdinJson, writeStdoutJson } from "@constellos/claude-code-kit/runners";
const input = await readStdinJson<PreToolUseHookInput>();

Hook Output

PreToolUse - Control execution:

{"hookSpecificOutput": {"hookEventName": "PreToolUse", "permissionDecision": "deny", "permissionDecisionReason": "Use gh cli instead"}}

{"hookSpecificOutput": {"hookEventName": "PreToolUse", "updatedInput": {"state": "Todo"}}}

PostToolUse - Provide feedback:

{"hookSpecificOutput": {"hookEventName": "PostToolUse", "additionalContext": "Lint errors found..."}}

Exit with no output to allow without modification.

Script Storage

Store complex hooks in .claude/hooks/ or project hooks/ directory:

.claude/
├── settings.json
└── hooks/
    └── my-hook.ts

Reference with:

"command": "bun $CLAUDE_PROJECT_DIR/.claude/hooks/my-hook.ts"

Examples

See these repositories for hook implementations:

Input modification: plugins/linear/hooks/
Permission decisions: plugins/github/scripts/
PostToolUse feedback: .claude/hooks/biome/

Debugging

For troubleshooting hook failures, see debugging.

Converted and distributed by TomeVault — claim your Tome and manage your conversions.

---name: claude-codehookdescription: Use this skill when you need to configure, create, or troubleshoot Claude Code hooks. This includes setting up PreToolUse hooks, PostToolUse hooks, UserPromptSubmit hooks, debugging hook failures, or any automation within Claude Code. Examples include "I want to run tests before every file edit", "My hook isn't firing", "1 out of 2 hooks ran", or "How do I create a hook that formats JSON output with jq?---# Claude Code HooksReference for creating and configuring Claude Code hooks. When uncertain about syntax or features, use the Task tool with `subagent_type='claude-code-guide'` to consult official documentation.## Hook Types| Type | Trigger | Use Cases ||------|---------|-----------|| PreToolUse | Before tool execution | Validate inputs, block operations, modify parameters || PostToolUse | After tool completes | Check results, run linters, provide feedback || UserPromptSubmit | When user sends message | Pre-process input, add context || Stop | Session ends | Cleanup, save state || SubagentStop | Subagent completes | Process results || PreCompact | Before context compaction | Save important state || Notification | System notification | Log events |## Configuration Files- `~/.claude/settings.json` - User-level (global)- `.claude/settings.json` - Project-level- `.claude/settings.local.json` - Local (not committed)- Plugin hooks: `plugins/<name>/hooks/hooks.json`## Hook Structure```json{ "hooks": { "PostToolUse": [ { "matcher": "Edit|Write", "hooks": [ { "type": "command", "command": "bun ./hooks/biome" } ] } ] }}```**Matcher Patterns**:- Simple: `"Write"`, `"Edit"`- Multiple: `"Edit|Write|MultiEdit"`- With args: `"Bash(npm:*)"`, `"Bash(osascript:*)|Bash(open:*)"`- MCP tools: `"mcp__linear__create_issue"`- Plugin MCP tools: `"mcp__plugin_<plugin>_<namespace>__<tool>"`- Claude AI MCP tools: `"mcp__claude_ai_<DisplayName>__<tool>"`- All three patterns: `"mcp__linear__create_issue|mcp__plugin_linear_linear__create_issue|mcp__claude_ai_Linear__save_issue"`## Hook InputCommands receive JSON on stdin:```json{ "tool_name": "Write", "tool_input": { "file_path": "/path/to/file.ts", "content": "..." }, "cwd": "/project/root", "session_id": "...", "transcript_path": "..."}```Parse in shell:```bashinput=$(cat)file_path=$(echo "$input" | jq -r '.tool_input.file_path')```Or use `@constellos/claude-code-kit/runners`:```typescriptimport { readStdinJson, writeStdoutJson } from "@constellos/claude-code-kit/runners";const input = await readStdinJson<PreToolUseHookInput>();```## Hook Output**PreToolUse** - Control execution:```json{"hookSpecificOutput": {"hookEventName": "PreToolUse", "permissionDecision": "deny", "permissionDecisionReason": "Use gh cli instead"}}``````json{"hookSpecificOutput": {"hookEventName": "PreToolUse", "updatedInput": {"state": "Todo"}}}```**PostToolUse** - Provide feedback:```json{"hookSpecificOutput": {"hookEventName": "PostToolUse", "additionalContext": "Lint errors found..."}}```Exit with no output to allow without modification.## Script StorageStore complex hooks in `.claude/hooks/` or project `hooks/` directory:```.claude/├── settings.json└── hooks/ └── my-hook.ts```Reference with:```json"command": "bun $CLAUDE_PROJECT_DIR/.claude/hooks/my-hook.ts"```## ExamplesSee these repositories for hook implementations:- Input modification: [plugins/linear/hooks/](plugins/linear/hooks/)- Permission decisions: [plugins/github/scripts/](plugins/github/scripts/)- PostToolUse feedback: [.claude/hooks/biome/](.claude/hooks/biome/)## DebuggingFor troubleshooting hook failures, see [debugging](references/debugging.md).---> Converted and distributed by [TomeVault](https://tomevault.io/claim/bendrucker) — claim your Tome and manage your conversions.

Frequently asked questions