I just had the same thing coming here looking for an answer.
Eventually looked in the build logs and in the Extract app intents metadata
(which had a green checkmark) I found this
Starting appintentsmetadataprocessor export
warning: At least one halting error produced during export. No AppIntents metadata have been exported and this target is not usable with AppIntents until errors are resolved.
warning: 'typeDisplayRepresentation' must directly instantiate a 'TypeDisplayRepresentation'
For me this was something like
static var typeDisplayRepresentation: TypeDisplayRepresentation {
TypeDisplayRepresentation(stringLiteral: "")
}
That used to work in some previous version of Xcode, updating it to
static var typeDisplayRepresentation: TypeDisplayRepresentation {
""
}
fixed it here, but might be good to check that log.