index.json shipped 604 of 817 descriptions truncated to their first line.
The cause was the inline regex parser in update-index.yml: it reconstructed
multi-line descriptions only for the YAML block-scalar styles ('>' and '|')
and silently dropped continuation lines for every other style.
A census of the corpus explains the blast radius:
block scalar (description: >-) 43
single-quoted multiline 278
plain unquoted multiline 496
single-line 0
So 774 of 817 skills (94.7%) used a style the parser mishandled. Commit
d56fc0a7 had fixed only the 43 block-scalar files, and CONTRIBUTING.md
recommends that one working style, which is why it stayed hidden.
- add tools/skill_frontmatter.py, the single PyYAML-backed loader
- add tools/generate-index.py so generation is testable outside CI, with
a --check mode for use as a gate
- delete the hand-rolled parsers from validate-skill.py (98 lines) and
validate-agentskills.py, routing both through the shared loader
- implement the reserved-word check that agentskills-skill.schema.json
names validate-agentskills.py as the enforcement point for
Verified by a differential harness against yaml.safe_load ground truth:
index-vs-source mismatches 606 -> 0.
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