Skill Frontmatter Configuration

Skill files support YAML frontmatter that controls execution behavior, tool access, and user interaction.

Frontmatter Options

---
argument-hint: "migration name"
context: fork
allowed-tools:
  - write_file
model: haiku
---

context: fork

Runs the skill in an isolated sub-agent context:

• Prevents verbose output from polluting the main conversation
• Essential for exploration/analysis skills (e.g., codebase analysis, brainstorming alternatives)
• Abandoned approaches in the fork don't influence subsequent implementation work
• The fork returns only a summary to the main conversation

allowed-tools

Restricts tool access during skill execution (principle of least privilege):

• Limit to file write operations to prevent destructive actions
• Prevent accidental deletion or modification of unrelated files
• Each skill gets only the tools it needs

argument-hint

Shows expected parameters during autocomplete:

• Prompts developers for required parameters when they invoke the skill without arguments
• Improves discoverability of skill parameters
• Example: argument-hint: "migration name" tells the developer to provide a migration name