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parser

parser

SkillParser — strict spec validation + tolerant field mapping.

The parser is the single chokepoint for converting raw frontmatter dicts into normalized SkillManifest instances. It runs two passes:

  1. Strict pass — validates required fields, length limits, naming rules.
  2. Tolerant pass — maps non-spec top-level fields to their canonical locations under metadata.diapason.* via FIELD_MAPPING.

The mapping table is data, not code paths. Adding support for a new vendor's fields means adding entries to FIELD_MAPPING — no logic changes.

Classes

SkillParseError

Bases: ValueError

Raised when a skill frontmatter cannot be parsed.

SkillParser

Parse SKILL.md frontmatter into a SkillManifest.

Two-pass design:

  • :meth:parse_frontmatter runs the strict pass + tolerant pass and returns a normalized :class:SkillManifest.
Methods:
parse_frontmatter 
parse_frontmatter(
    frontmatter: Dict[str, Any],
    *,
    markdown_content: str = "",
) -> SkillManifest

Parse a frontmatter dict, returning a SkillManifest.

Runs strict validation first, then applies tolerant field mapping.

Source code in src/diapason/skills/parser.py 
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def parse_frontmatter(
    self,
    frontmatter: Dict[str, Any],
    *,
    markdown_content: str = "",
) -> SkillManifest:
    """Parse a frontmatter dict, returning a SkillManifest.

    Runs strict validation first, then applies tolerant field mapping.
    """
    self._validate_strict(frontmatter)
    return self._build_manifest(frontmatter, markdown_content)