The standard requires only name+description; additional top-level keys are
permitted metadata. Fixes:
- validator no longer counts extra top-level keys as violations (reports them
as informational only).
- angle-bracket check now ignores YAML block-scalar indicators (`>`, `>-`,
`|`), which were false-positiving on multi-line descriptions; no skill has
genuine angle-bracket content.
- schema additionalProperties false -> true to match.
Audit result: 817/817 compliant.
- tools/agentskills-skill.schema.json: strict JSON Schema for the
agentskills.io SKILL.md frontmatter standard (name+description required;
optional license/compatibility/metadata/allowed-tools; no other top-level
keys).
- tools/validate-agentskills.py: read-only compliance validator (also checks
name==directory and the no-angle-brackets rule).
Mahipal