My understanding is that the

docker.Image()

should accept a type

Output

in the

build.args

based on the source code for

pulumi_docker

. This seems to not be a correct understanding though. I could also be misunderstanding what

pulumi.Input[Mapping[str, pulumi.Input[str]]]

means.

pulumi.Input[T]

is an alias for

Union[T, Awaitable[T], Output[T]]

so passing in an

Output

is one option, but you can also just pass in a dict.