Skills

Skills.index() returns SkillInfo records and Skills.load(name) returns a Skill. FileSystemSkills implements the protocol for SKILL.md directories.

Pass the source through Runtime(skills=...). Agent filtering and permission handling occur in Runtime.

Runtime adds allowed skill names and index descriptions to one execution-environment system block. Calling skill(name) returns the body as a tool result. The body is therefore loaded on demand rather than copied into every sample. Agent.skills=None exposes the catalogue, a list is an allowlist, and [] disables the tool.