[Phase 4] Hook packs and AgentKit reference publishing

[mrgoonie]

Depends on

• Epic [Epic] SkillX Marketplace & Agent-Native Platform Roadmap #31

• Phase 3 [Phase 3] Personal kits, installer, lockfile and multi-device sync #35

Objective

Safely distribute executable hook packs and prove coexistence with mature AgentKit installs.

Scope

• Hook-pack schema.
• Runtime capability/event compatibility.
• First harness hook activation lifecycle.
• Review/security policy for executable content.
• Conflict detection.
• AgentKit standalone hook-pack export.
• Curated AgentKit SkillX bundle only after closure is complete.

Implementation tasks

• Define hook-pack manifest.
• Define runtime event/capability vocabulary.
• Define registration identity/conflict rules.
• Validate entrypoint/support dependency closure.
• Surface interpreter/runtime requirements.
• Plan hook registration separately from file writes.
• Require explicit apply before activation.
• Add executable digest/update warnings.
• Add requirement-change warnings.
• Add hook review/quarantine policy.
• Detect existing externally-managed files/registrations.
• Reject incompatible collisions rather than filename-dedup.
• Export one standalone AgentKit hook pack.
• Test mixed AgentKit + third-party collection.
• Test coexistence on a machine already using AgentKit.
• Define criteria for an AgentKit curated SkillX bundle.

Acceptance criteria

• Preview/discovery never executes code.
• Missing required hook capability blocks activation.
• AgentKit-owned content is not silently taken over.
• Mixed collection install/update/remove is deterministic.

Milestone: product beta.