{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "manni:graph-strict:1.0.0",
  "title": "manni graph strict overlay v1.0.0",
  "description": "The strict overlay for manni:graph:1.0.0. Stack it beside the open vocabulary, which owns the closed `graph` block and its iiRDS enums. It narrows section keys to heading slugs and lineage references to single tokens.",
  "additionalProperties": true,
  "type": "object",
  "properties": {
    "graph": {
      "description": "Strict narrows `sections` keys, `revision-of` and `derived-from`. Every other member of the block passes as the open vocabulary reads it.",
      "properties": {
        "sections": {
          "propertyNames": {
            "pattern": "^[\\p{Ll}\\p{Lm}\\p{Lo}\\p{M}\\p{Nd}_-]+$",
            "description": "A heading slug of lowercase letters, caseless letters and their marks, digits, `_` and `-`. It admits slugs from scripts without case, such as Han, Arabic and Devanagari. The pattern uses Unicode property escapes, so a validator must compile it with the ECMA-262 `u` flag, as Ajv does for a 2020-12 schema."
          }
        },
        "revision-of": {
          "$ref": "#/$defs/refList"
        },
        "derived-from": {
          "$ref": "#/$defs/refList"
        }
      }
    }
  },
  "$defs": {
    "refList": {
      "pattern": "^\\S(?:.*\\S)?$",
      "items": {
        "pattern": "^\\S(?:.*\\S)?$"
      },
      "description": "A path or URL on one line with no surrounding space, alone or in each item of the list. A path may contain spaces."
    }
  }
}