<CodeSystem xmlns="http://hl7.org/fhir">
  <id value="NHSDigital-http-error-codes" />
  <url value="https://fhir.nhs.uk/CodeSystem/http-error-codes" />
  <version value="1.0.0" />
  <name value="HttpErrorCodes" />
  <status value="active" />
  <date value="2022-01-25T00:00:00+00:00" />
  <publisher value="NHS Digital" />
  <contact>
    <name value="Interoperability Team" />
    <telecom>
      <system value="email" />
      <value value="interoperabilityteam@nhs.net" />
      <use value="work" />
    </telecom>
  </contact>
  <description value="A CodeSystem that identifies the HTTP Error Codes in response to a request." />
  <copyright value="Copyright © 2022 NHS Digital" />
  <caseSensitive value="true" />
  <content value="complete" />
  <concept>
    <code value="SEND_BAD_REQUEST" />
    <display value="400: The API was unable to process the request." />
    <definition value="The API has given a 400 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_BAD_REQUEST" />
    <display value="400: The Receiver was unable to process the request." />
    <definition value="The Receiver has given a 400 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_BAD_REQUEST" />
    <display value="400: The Proxy was unable to process the request." />
    <definition value="The Proxy has given a 400 response internally to the Senders request." />
  </concept>
  <concept>
    <code value="BAD_REQUEST" />
    <display value="400: The Server was unable to process the request." />
    <definition value="The Server has given a 400 response to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_UNAUTHORIZED" />
    <display value="401: The API deemed you unauthorized to make this request." />
    <definition value="The API has given a 401 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_UNAUTHORIZED" />
    <display value="401: The Receiver deemed you unauthorized to make this request." />
    <definition value="The Receiver has given a 401 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_UNAUTHORIZED" />
    <display value="401: The Proxy deemed you unauthorized to make this request." />
    <definition value="The Proxy has given a 401 response internally to the Senders request." />
  </concept>
  <concept>
    <code value="UNAUTHORIZED" />
    <display value="401: The Server deemed you unauthorized to make this request." />
    <definition value="The Server has given a 401 response to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_FORBIDDEN" />
    <display value="403: Failed to authenticate with the API." />
    <definition value="The API has given a 403 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_FORBIDDEN" />
    <display value="403: Failed to authenticate with the Receiver." />
    <definition value="The Receiver has given a 403 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_FORBIDDEN" />
    <display value="403: Failed to authenticate with the Receiver." />
    <definition value="The Proxy has given a 403 response to the Senders request." />
  </concept>
  <concept>
    <code value="FORBIDDEN" />
    <display value="403: Failed to Authenticate with the Server." />
    <definition value="The Server has given a 403 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_NOT_FOUND" />
    <display value="404: The Proxy was unable to find the specified resource." />
    <definition value="The Proxy has given a 404 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_NOT_FOUND" />
    <display value="404: The Receiver was unable to find the specified resource." />
    <definition value="The Receiver has given a 404 response to the Senders request." />
  </concept>
  <concept>
    <code value="NOT_FOUND" />
    <display value="404: The Server was unable to find the specified resource." />
    <definition value="The Server has given a 404 response to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_METHOD_NOT_ALLOWED" />
    <display value="405: This API doesnt allow this method." />
    <definition value="The API has given a 405 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_METHOD_NOT_ALLOWED" />
    <display value="405: The Receiver doesnt allow this method." />
    <definition value="The Receiver has given a 405 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_METHOD_NOT_ALLOWED" />
    <display value="405: The Proxy doesnt allow this method." />
    <definition value="The Proxy has given a 405 response to the Senders request." />
  </concept>
  <concept>
    <code value="METHOD_NOT_ALLOWED" />
    <display value="405: This method is not allowed." />
    <definition value="The Server has given a 405 response to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_NOT_ACCEPTABLE" />
    <display value="406: Senders message had an incorrect content type defined for a response." />
    <definition value="The API has given a 406 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_NOT_ACCEPTABLE" />
    <display value="406: Message had an incorrect content type defined for a response." />
    <definition value="The Server has given a 406 response to the Senders request." />
  </concept>
  <concept>
    <code value="NOT_ACCEPTABLE" />
    <display value="406: Senders message had an incorrect content type defined for a response." />
    <definition value="The Server has given a 406 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_TIMEOUT" />
    <display value="408: The request timed out to the receiver." />
    <definition value="The Receiver has given a 408 resonse to the Senders request" />
  </concept>
  <concept>
    <code value="PROXY_TIMEOUT" />
    <display value="408: The request timed out internally." />
    <definition value="The Proxy has given a 408 response internally to the Senders request." />
  </concept>
  <concept>
    <code value="TIMEOUT" />
    <display value="408: The request timed out." />
    <definition value="The Server has given a 408 response to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_CONFLICT" />
    <display value="409: The API identified a conflict." />
    <definition value="The API has given a 409 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_CONFLICT" />
    <display value="409: The Receiver identified a conflict." />
    <definition value="The Receiver has given a 409 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_CONFLICT" />
    <display value="409: The Proxy identified a conflict." />
    <definition value="The Proxy has given a 409 response to the Senders request." />
  </concept>
  <concept>
    <code value="CONFLICT" />
    <display value="409: The Server identified a conflict." />
    <definition value="The Server has given a 409 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_UNSUPPORTED_MEDIA_TYPE" />
    <display value="415: The request is in an unsupported format." />
    <definition value="The Receiver has given a 415 response to the Senders request." />
  </concept>
  <concept>
    <code value="UNSUPPORTED_MEDIA_TYPE" />
    <display value="415: The request is in an unsupported format." />
    <definition value="The Receiver has given a 415 response to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_UNPROCESSABLE_ENTITY" />
    <display value="422: Message was not malformed but deemed unprocessable by the API." />
    <definition value="The API has given a 422 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_UNPROCESSABLE_ENTITY" />
    <display value="422: Message was not malformed but deemed unprocessable by the Receiver." />
    <definition value="The Receiver has given a 422 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_UNPROCESSABLE_ENTITY" />
    <display value="422: Message was not malformed but deemed unprocessable by the Proxy." />
    <definition value="The Proxy has given a 422 response to the Senders request." />
  </concept>
  <concept>
    <code value="UNPROCESSABLE_ENTITY" />
    <display value="422: Message was not malformed but deemed unprocessable by the server." />
    <definition value="The Server has given a 422 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_TOO_MANY_REQUESTS" />
    <display value="429: Too many requests have been made by this source to the Proxy in a given amount of time." />
    <definition value="The Proxy has given a 429 response internally to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_TOO_MANY_REQUESTS" />
    <display value="429: Too many requests have been made by this source to the API in a given amount of time." />
    <definition value="The API has given a 429 response to the Senders request." />
  </concept>
  <concept>
    <code value="TOO_MANY_REQUESTS" />
    <display value="429: Too many requests have been made by this source in a given amount of time." />
    <definition value="The Server has given a 429 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_SERVER_ERROR" />
    <display value="500: The Receiver has encountered an error processing the request." />
    <definition value="The Receiver has given a 500 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_SERVER_ERROR" />
    <display value="500: The Proxy has encountered an error processing the request." />
    <definition value="The Proxy has given a 500 response to the Senders request." />
  </concept>
  <concept>
    <code value="SERVER_ERROR" />
    <display value="500: The Server has encountered an error processing the request." />
    <definition value="The Server has given a 500 response to the Senders request." />
  </concept>
  <concept>
    <code value="SEND_NOT_IMPLEMENTED" />
    <display value="501:The Request was not recognized by the API." />
    <definition value="The API has given a 501 response to the Senders request." />
  </concept>
  <concept>
    <code value="REC_NOT_IMPLEMENTED" />
    <display value="501: The Request was not recognized by the Receiver." />
    <definition value="The Receiver has given a 501 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_NOT_IMPLEMENTED" />
    <display value="501: The Request was not recognized by the Proxy." />
    <definition value="The Proxy has given a 501 response to the Senders request." />
  </concept>
  <concept>
    <code value="NOT_IMPLEMENTED" />
    <display value="501: The Request was not recognized by the server." />
    <definition value="The Server has given a 501 response to the Senders request." />
  </concept>
  <concept>
    <code value="PROXY_UNAVAILABLE" />
    <display value="503: An internal component is unavailable" />
    <definition value="The Proxy has given a 503 response internally to the Senders request." />
  </concept>
  <concept>
    <code value="REC_UNAVAILABLE" />
    <display value="503: The Receiver is currently unavailable." />
    <definition value="The Receiver has given a 503 response to the Senders request." />
  </concept>
  <concept>
    <code value="UNAVAILABLE" />
    <display value="503: The Server is currently unavailable." />
    <definition value="The Receiver has given a 503 response to the Senders request." />
  </concept>
</CodeSystem>