Skill Start

Skill Start

Configuration for skill start hooks that trigger when subagents (skills) start.

This allows configuring different commands for different skill types using pattern matching. Commands run when a skill/subagent begins execution.

Pattern Matching Rules

• Patterns are matched in the order they appear in the configuration - First matching pattern’s commands are executed - Use ”*” to match all skills (put last as fallback) - Glob patterns support: *, ?, [abc], [a-z], {foo,bar}

Environment Variables

The following environment variables are available in skill start hooks: - CONCLAUDE_SKILL_NAME - The skill/agent type name - CONCLAUDE_AGENT_ID - Unique agent identifier - CONCLAUDE_AGENT_TRANSCRIPT_PATH - Path to subagent’s transcript - CONCLAUDE_SESSION_ID - Current session ID - CONCLAUDE_TRANSCRIPT_PATH - Main transcript file path - CONCLAUDE_HOOK_EVENT - Always “SubagentStart” - CONCLAUDE_CWD - Current working directory

Configuration Properties

commands

Map of skill name patterns to command configurations.

Each key is a glob pattern that matches against the skill/agent type. Commands are executed in the order they appear when the pattern matches.

Pattern examples: - "*" - Matches all skills (wildcard) - "coder" - Exact match for coder skill - "test*" - Matches any skill starting with “test” - "*coder" - Matches any skill ending with “coder”

Command options: - run: (required) Command to execute - showStdout: (optional) Show stdout to user/Claude. Default: false - showStderr: (optional) Show stderr to user/Claude. Default: false - message: (optional) Custom error message on non-zero exit - maxOutputLines: (optional) Limit output lines. Range: 1-10000 - timeout: (optional) Command timeout in seconds. Range: 1-3600

Attribute	Value
Type	object
Default	{}

Nested Types

This section uses the following nested type definitions:

SkillStartCommand Type

Configuration for individual skill start commands with optional messages

Properties:

Property	Type	Default	Description
maxOutputLines	`integer	null`	null
message	`string	null`	null
notifyPerCommand	`boolean	null`	null
run	string	-	The shell command to execute
showCommand	`boolean	null`	true
showStderr	`boolean	null`	null
showStdout	`boolean	null`	null
timeout	`integer	null`	null

Complete Examples

Here are complete configuration examples for the skillStart section:

skillStart: commands: # Exact match - only runs when "coder" skill starts "coder": - run: ".claude/scripts/coder-init.sh" showStdout: true

# Glob pattern - runs for any skill starting with "test" "test*": - run: ".claude/scripts/test-env-check.sh"

# Wildcard - runs for ALL skills "*": - run: ".claude/scripts/log-skill.sh" showCommand: false

See Also

• Configuration Overview - Complete reference for all configuration options