AsciiDoc

Install the extension:

yarn add asciidoctor-kroki

Enable the extension in antora-playbook.yml. Beware, it is asciidoc extension, not antora extension, just add another key:

antora:
  extensions:
    ...
asciidoc:
  extensions:
    asciidoctor-kroki

Refer to a partial with the puml file extension:

[plantuml,target=ab-partial-1,format=svg]
----
include::partial$puml/alice-bob.puml[]
----

Write down the puml code and render it directly:

[plantuml,ab-partial-all-1,svg]
----
alice -> bob
bob -> alice
----