Success
message.text— a human-readable summary.message.token— a stable machine-readable key. Branch on this rather than onmessage.text, which may change wording or be localised.content.data— the resource(s) returned by the endpoint.content.metadata— context such as the date and date-time formats used indata.
Errors
Errors use the same envelope. Thetoken identifies the error, and tokenArguments carries any parameters needed to render a message.