skill-link

name	skill-link
description	Build and query the parent/child dependency graph across all skills in a marketplace. Use when auditing for overlapping functionality, finding consumers of a skill, or answering "what depends on X?" without storing a separate children list. Do not use this skill to edit skill metadata or create new skills.

Skill Link

Trigger

• Use when the caller wants a structured parent/child map across every skill under skills/.
• Use when checking whether a proposed new skill overlaps existing ones.
• Use when asked "which skills depend on <id>?" — children are derived, not stored.
• Do not use to write or modify any skill.yaml / SKILL.md files.

Inputs

• skills_root: filesystem path to the marketplace skills/ directory. Defaults to "skills" relative to the current working directory.
• skill_id: optional. When provided, return only the node for that skill (its declared parents plus derived children). Otherwise return the full graph.

Workflow

1. Resolve skills_root and enumerate every immediate subdirectory that contains a skill.yaml.
2. For each skill, load skill.yaml and record id plus parents (an empty list when the field is absent).
3. Build a map children: id -> [ids that declare id as a parent] by inverting the parents relation.
4. If skill_id is supplied, return only the single node for that id. Otherwise return a sorted list of all nodes.
5. Flag any parents entry that does not match a known skill id as a warning — do not error; surfacing dangling references is part of the audit value.

Outputs

• nodes: list of {id, parents, children} objects, sorted by id.
• warnings: list of human-readable strings for dangling parent references or malformed skill.yaml files.

Failure / Escalation

• If skills_root does not exist, fail cleanly with a single warning and return an empty nodes list.
• If skill_id is supplied but not found, return nodes: [] and a warning naming the missing id.
• If a skill.yaml fails to parse, skip it, add a warning, and continue — one bad file should not break the audit.

Tool Contract

• Read tool.json for the authoritative schema.
• skills_root is optional (default "skills"); skill_id is optional.
• A runnable reference implementation lives in examples/basic.py.