← all problem types

unknown_contact_ref

422 Unprocessable Content   A subscription references a contact ref that no contacts[] item declares.

When you get it

A subscription references a contact ref that no contacts[] item declares. It is always answered with HTTP 422 - one code means one status, so a client may key its handling on either.

Fields it carries

Inside each errors[] entry, beside pointer:

pointer

RFC 6901 JSON Pointer to the offending value in the request body.

ref

The inline reference that did not resolve.

declared

The references the request itself declared, for comparison with the one that did not resolve.

A field is omitted when the server genuinely does not know it - an absent member is never the same as an empty one.

How to fix it

The request was well-formed but a value is not acceptable. The fields above name the offending value and what would be accepted - fix the request and retry.

Shape

{
  "type":   "https://api2.host-tracker.com/problems/unknown-contact-ref",
  "title":  "A subscription references a contact ref that no contacts[] item declares.",
  "status": 422,
  "code":   "unknown_contact_ref",
  "errors": [
    { "pointer": …, "ref": …, "declared": … }
  ]
}