{
  "validationRules": [
    {
      "id": "vrule_lead_post_convert_read_only",
      "objectApiName": "Lead",
      "name": "Lead_Post_Convert_Readonly",
      "description": "Prevents edits to converted Lead records through generic validation metadata.",
      "active": true,
      "condition": "PRIORVALUE(IsConverted) = TRUE",
      "errorMessage": "This lead has already been converted. No further changes are allowed."
    }
  ]
}