ref-sp-agents-shareable-skillslisted

# Shareable Skills (Sharing Spec) ## Purpose Define the single normative spec for how a repo **names**, **describes in frontmatter**, **scopes**, **shares**, **vendors**, and **validates for export** its skills. This is the source of truth for that standardization; other skills point here instead of restating it. The mechanism is portable — any repo can adopt it — while the concrete values it fills in (owner prefix, owner, domain registry) are that repo's own. The values shown throughout are this repo's instantiation. This skill owns the **sharing-spec** rules. It does **not** own general skill-quality rules (trigger quality, structure, progressive disclosure) — those belong to the repo's skill-authoring skill (`ref-sp-agents-skills-authoring` here). The two are complementary and independent; neither hard-depends on the other (see the spec's "Relationship" section). > **Schema status (this repo):** the migration is complete here. Every skill is owner-prefix renamed, > all portability fields live under the `metadata.shareable-skills.*` namespace, and the validator > runs at Phase 3 (hard-fail). A repo adopting this spec fresh starts at whatever phase it sets in > its registry. `./references/spec.md` §9 keeps this repo's migration history. ## When to use this skill - Naming or renaming a skill (owner-prefix / domain / template / topic grammar). - Setting `shareable-skills.owner`, `shareable-skills.domain`, `shareable-skills.tags`, `shareable-skills.visibility`, or the t