Name of the function to be called. Required and must be 'GetStock' in this case. If omitted, an error 'E001: Parameter Action is mandatory' is returned. If an unknown function string is provided, an error message 'E008: Invalid Action' is returned.

If provided, it must be 'JSON' or 'XML'. If not provided, 'XML' is assumed.

The current time in ISO8601 format relative to UTC (e.g., Timestamp = 2015-04-01T10:00:00+02:00 for Berlin), so that calls cannot be replayed by a third party intercepting them (i.e., calls too far in the past or future will produce an error message). Required. If not provided, the error message 'E001: Parameter Timestamp is mandatory' appears. If the timestamp is too old or in the future, an error message "E003: Timestamp has expired" is returned.

The ID of the user making the call. The list of authorized users is maintained in the Seller Center web interface under General Settings / Manage Users.

The API version against which this call will be executed, in major-dot-minor format. It must currently be 1.0, although the actual API version is 2.6.20. If omitted, an error message "E001: Parameter Version is mandatory" is returned.

The cryptographic signature that authenticates the request. A caller must create this value by calculating the SHA256 hash of the request, using the API key of the user specified in the UserID parameter. Required. If omitted, an error message "E001: Parameter Signature is mandatory" is returned. If the signature is incorrect, an 'E007: Login failed' error message for signature mismatch is returned.