{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://openvisual.org/schema/halo/1.0",
  "title": "OVS: Halo",
  "description": "Ring artifacts around light sources. Common in cataract, VSS, and corneal conditions.",
  "allOf": [
    { "$ref": "https://openvisual.org/schema/symptom-base/1.0" },
    {
      "type": "object",
      "properties": {
        "ovs_type":   { "const": "ovs:halo" },
        "rainbow":    { "type": "boolean", "description": "Whether the halo shows spectral / rainbow colors" },
        "near_ring":  { "type": "boolean", "description": "Whether a secondary near-field ring is visible" }
      }
    }
  ]
}