Misleading message: "Key is not included in URL"

Great gem, but the error message "Key is not included in URL" seems misleading to me for some reasons.

I) It is not clear whar is meant by "key" (I would suggest "id").
II) The message references a concrete problem in the URL, a missing key, which might not be true (e.g. a wrong key might be the problem as well).
III) The error could have happened in the data section as well.
IV) This message is returned whenever something goes wrong with the id (e.g. wrong type of id field in the data section), see example

Example: The following patch request to the correct url (and id) might cause this error message due to an invalid data type (int) for id. It has nothing to do with a "not included" key in the url.

{
data: {
"type": "articles",
"id": 1,
"attributes": {
"title": "updated title"
}
}
}

The request is invalid because of the wrong type (int) for "id". It MUST be string (conforming to json api), and jsonapi-resources correctly refuses to process this request, but with this misleading error message.

Suggestion for this Message: "id field is invalid or does not match the id given in the URL."

Search the codebase for the exact message "Key is not included in URL" and trace the validation path exercised by the example payload. Reproduce the invalid integer id case, then update the wording so it describes an invalid or mismatched id and verify the relevant request behavior with the existing tests.