OptionalbodyContains message body if success === true.
The command requested.
OptionalmessageIf success === false, this should always be provided. Otherwise, may (or may not) contain a success message.
OptionalmetadataContains extra information that plugin can include to be passed on
OptionalperformanceExposes information about the performance of this request-response pair.
Sequence number of the request message.
Sequence number of the message
Outcome of the request.
One of "request", "response", or "event"
Response object for a SignatureHelpRequest.