{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "google:okf:0.1",
  "title": "Open Knowledge Format (OKF) v0.1",
  "description": "Frontmatter schema for OKF v0.1 concept files. OKF requires only `type`; all other fields are recommended, and unknown keys are explicitly tolerated. See https://github.com/GoogleCloudPlatform/knowledge-catalog/blob/main/okf/SPEC.md",
  "type": "object",
  "required": ["type"],
  "additionalProperties": true,
  "properties": {
    "type": {
      "type": "string",
      "minLength": 1,
      "description": "A short string identifying the kind of concept. Used for routing, filtering, and presentation."
    },
    "title": {
      "type": "string",
      "description": "Human-readable display name. If omitted, consumers MAY derive a title from the filename."
    },
    "description": {
      "type": "string",
      "description": "Single-sentence summary used for indexing and previews."
    },
    "resource": {
      "type": "string",
      "format": "uri",
      "description": "A URI uniquely identifying the underlying asset. Absent for abstract concepts."
    },
    "tags": {
      "type": "array",
      "items": { "type": "string" },
      "description": "Short strings for categorization."
    },
    "timestamp": {
      "type": "string",
      "format": "date-time",
      "description": "ISO 8601 datetime of last meaningful change."
    }
  }
}