---
title: "CS: Response Code"
canonical: "https://wiki.patientsknowbest.com/space/api/3365077057/CS%3A%20Response%20Code"
format: markdown
---
[http://fhir.patientsknowbest.com/codesystem/response-code](http://fhir.patientsknowbest.com/codesystem/response-code)

[https://www.hl7.org/fhir/STU3/codesystem.html](https://www.hl7.org/fhir/STU3/codesystem.html)

## description

When PKB returns an error, we will try to include an [OperationOutcome](https://www.hl7.org/fhir/STU3/operationoutcome.html) with a meaningful error code.

## concepts

- concept[0]
  - code = ACC_TOKEN_EXPIRED
  - display = Access token expired
  - definition = Your access token has expired. If you have a refresh token, you can use this to try to obtain a new access token.
- concept[1]
  - code = ACCESS_FROZEN_OUTWARD
  - display = Access frozen outward
  - definition = The patient who is making the request has had their access frozen.
- concept[2]
  - code = API_SESSION_EXPIRED
  - display = API session expired
  - definition = Some API sessions expire after a predefined amount of time. If your session has expired you are not able to use an existing access token, and you are not able to use a refresh token to obtain a new access token.
- concept[3]
  - code = API_SESSION_INVALID
  - display = API session invalid
  - definition = An API session can be invalidated for a few reasons. For example, if a refresh token is used more than once.
- concept[4]
  - code = BAD_AUTHENTICATION
  - display = Bad authentication
  - definition = You did not provide a valid access token. For example, perhaps you forgot to include the Authorization header with your request.
- concept[5]
  - code = USER_TYPE_NOT_PERM
  - display = User type not permitted
  - definition = You attempted to call an endpoint which is not permitted for your user type.