generated: '2026-07-19'
method: searched
source: https://klook.gitbook.io/openapi/getting-started/errors.md
docs: https://klook.gitbook.io/openapi/getting-started/errors.md
format: custom
description: >-
  Klook's Open API (OCTO) uses a deliberately narrow HTTP status model: every
  request returns either 200 OK or 400 Bad Request, with the real error
  discriminator carried in the `error` field of the JSON body. This is NOT
  RFC 9457 problem+json — the envelope is a bare JSON object with `error` and
  `errorMessage`, plus optional context attributes naming the offending
  identifier.
envelope:
  content_type: application/json
  http_status_model: >-
    200 OK on success, 400 Bad Request on any failure. The docs note 403
    Forbidden for an invalid or deactivated token.
  fields:
  - name: error
    required: true
    description: The error code. See error_codes[] below.
  - name: errorMessage
    required: true
    description: >-
      A human readable error message, translated according to the language
      provided in the Accept-Language request header.
  - name: <context attribute>
    required: false
    description: >-
      Optional additional field echoing the offending value, e.g. productId,
      optionId, unitId, availabilityId. Present only for the codes listed below.
  example:
    error: INVALID_PRODUCT_ID
    errorMessage: The Product ID was invalid or missing
    productId: '123'
error_codes:
- code: INVALID_PRODUCT_ID
  description: Missing or invalid productId in the request
  context_attribute: productId
  example:
    error: INVALID_PRODUCT_ID
    errorMessage: The Product ID was invalid or missing
    productId: '123'
- code: INVALID_OPTION_ID
  description: Missing or invalid optionId in the request
  context_attribute: optionId
  example:
    error: INVALID_OPTION_ID
    errorMessage: The Option ID was invalid or missing
    optionId: '321'
- code: INVALID_UNIT_ID
  description: Missing or invalid unitId in the request
  context_attribute: unitId
  example:
    error: INVALID_UNIT_ID
    errorMessage: The Unit ID was invalid or missing
    unitId: senior-123678
- code: INVALID_AVAILABILITY_ID
  description: Missing or invalid availabilityId in the request
  context_attribute: availabilityId
  example:
    error: INVALID_AVAILABILITY_ID
    errorMessage: The Availability ID was invalid or missing
    availabilityId: '2020-01-01T10:30+08:00'
- code: INVALID_BOOKING_UUID
  description: >-
    Missing or invalid booking uuid; or, when confirming a booking, the booking
    reservation may have already expired.
  context_attribute: null
- code: BAD_REQUEST
  description: >-
    The request body is not formatted correctly, has missing required fields, or
    one or more data types are incorrect.
  context_attribute: null
- code: UNPROCESSABLE_ENTITY
  description: >-
    The request body is technically correct but cannot be processed for other
    reasons — e.g. cancelling a booking after the cancellation cutoff has
    elapsed, or no inventory available to reserve during Booking Reservation.
  context_attribute: productId
  example:
    error: UNPROCESSABLE_ENTITY
    errorMessage: Activity inventory not available
    productId: '123'
  remediation: >-
    On Booking Reservation this is the documented response when there is no
    inventory or the slot cannot be reserved. Re-run Availability Check to get a
    fresh availabilityId before retrying.
- code: INTERNAL_SERVER_ERROR
  description: The backend server is down or there is a network outage.
  context_attribute: null
- code: UNAUTHORIZED
  description: >-
    No API key was sent in the Authorization header to an endpoint that requires
    authentication.
  context_attribute: null
- code: FORBIDDEN
  description: >-
    The API key sent was invalid or has been revoked by the backend system, or
    the caller is trying to access an endpoint/resource they do not have access
    to.
  context_attribute: null
  http_status: 403
related:
  problem_types: errors/klook-problem-types.yml
  conventions: conventions/klook-conventions.yml
  authentication: authentication/klook-authentication.yml