Audit: ./src/skills

[avoidwork]

Audit Summary

Scanned 6 files in ./src/skills for bugs, security vulnerabilities, and performance issues.

Findings

Severity	Count
Critical	1
High	2
Medium	2
Low	1

Detailed Findings

Critical

File	Line	Issue
discoverer.js	29, 50, 63	Unsafe YAML parsing — yaml.load() can execute arbitrary JavaScript from crafted SKILL.md files (e.g., !!js/function tags). Should use safe schema: yaml.load(yamlStr, { schema: yaml.JSON_SCHEMA }) or equivalent.

High

File	Line	Issue
registry.js	51-54	Silently dropped skills — Invalid (non-skip) skills are excluded from the results array but only logged to #errors. The discover() return value is inconsistent with register() which always returns results for all discovered skills. Callers have no way to know these skills were rejected without calling getErrors().
validator.js	110	Input mutation — skill.name = String(skill.name) mutates the caller's object. Side effect that could cause issues if the caller reuses the object.

Medium

File	Line	Issue
discoverer.js	179	Shadowing logic asymmetry — Only overrides when new skill is in .agents/skills. If project-level skill is discovered first, user-level skill is silently dropped. Should check both directions.
registry.js	140	Sync I/O in async context — readFileSync in getSkillBody() blocks the event loop. Acceptable for small files but could be problematic for large SKILL.md files.

Low

File	Line	Issue
discoverer.js	92-100	Sync FS operations — readdirSync, statSync, existsSync, readFileSync throughout. Acceptable for skills directory (small scope) but worth noting for consistency.

Clean Files

• index.js — Re-exports only, no issues
• permissions.js — Clean permission resolution logic
• types.js — Clean Zod schemas, no issues