AgentSkills management utilities

[enyst]

Summary

Add first-class AgentSkills management utilities in the SDK (install/uninstall/list/enable/disable) to complement the existing AgentSkills loader. This would provide the missing “package management” layer for skills directories that follow the AgentSkills spec.

Background

Current state in the SDK:

• AgentSkills format is supported via SKILL.md loaders (load_skills_from_dir, load_user_skills, load_public_skills).
• Public skills are loaded by cloning OpenHands/extensions into a local cache.
• There is no dedicated API to install, uninstall, list, or enable/disable AgentSkills.
• Enable/disable is effectively handled at runtime via AgentContext(load_user_skills=..., load_public_skills=...) or custom filtering.

Meanwhile, the new installed plugin utilities (#2031) cover plugin install/uninstall/list/update, but do not address AgentSkills packages directly.

Goals

• Provide a management layer for AgentSkills directories that follows the AgentSkills spec.
• Enable CLI workflows like /skills install ..., /skills list, and allow persistent enable/disable.
• Keep AgentSkills separate from plugin installs (no manifest required; skill root = SKILL.md).

Proposed API (example)

install_skill(source, ref=None, repo_path=None, installed_dir=None, force=False)
uninstall_skill(name, installed_dir=None)
list_installed_skills(installed_dir=None)
get_installed_skill(name, installed_dir=None)
update_skill(name, installed_dir=None)

Potential storage:

• ~/.openhands/skills/installed/ + metadata file (e.g. .installed.json)

Non-goals

• Replacing plugin install utilities
• Defining marketplace search UX (should live in CLI/UX layers)

Motivation

This unblocks CLI features (enable/disable global skills, /skills install, slash menu) while keeping the SDK’s skill loading semantics consistent with the AgentSkills spec.