Error Responses

When a query results in an error, an RDAP server is not required to send an RDAP error response but doing so is considered good practice.

Responses to errors in RDAP mirror the HTTP status code. Like all other RDAP responses, these are to have the content-type: application/rdap+json header and the rdapConformance array. The following is a very simple example:

{
  "rdapConformance" : [ "rdap_level_0" ],
  "errorCode": 420,
  "title": "Enhance Your Calm",
  "description":
  [
    "Chill out!",
    "Srsly, dude."
  ]
}

The response can have the following JSON data structures, including the common response structures of rdapConformance and notices array.

NameValue
rdapConformance(REQUIRED) a common type defined here
noticesa common type defined here
errorCode(REQUIRED) an integer matching the HTTP status code
titlea string specifying the title of the error
descriptionan array of strings describing the error
langa lang sting

Though rarely used, the error response may also have a notices array. The following is a complete example from RFC 9083:

{
  "rdapConformance" :
  [
    "rdap_level_0"
  ],
  "notices" :
  [
    {
      "title" : "Beverage Policy",
      "description" :
      [
        "Beverages with caffeine for keeping horses awake."
      ],
      "links" :
      [
        {
          "value" : "https://example.net/ip/192.0.2.0/24",
          "rel" : "alternate",
          "type" : "text/html",
          "href" : "https://www.example.com/redaction_policy.html"
        }
      ]
    }
  ],
  "lang" : "en",
  "errorCode": 418,
  "title": "Your beverage choice is not available",
  "description":
  [
    "I know coffee has more ummppphhh.",
    "Sorry, dude!"
  ]
}