Handler Types

Three common skill handler shapes:

Handler kind	What it is	When to use
Inline function	Local handler code	Logic-heavy skills with validation or tool orchestration
Sub-agent	Delegate to another agent	When the skill needs a separate reasoning loop
Prompt template	Prompt-only transformation	Cheap, stateless competencies

Pick by cost:

• prompt template: cheapest
• inline function: moderate
• subagent: most expensive

Start with the cheapest shape that gives the behavior you need.