AsyncAPI specs MUST include at least one main contact under the info.contact section.
The spec only allows to include one contact there, but it MAY also include additional contacts using extension fields. In case this is done, it MUST use the extension field x-additional-responsibles.
For example:
...
info:
...
contact:
name: "Main point of contact"
email: "[email protected]"
x-additional-responsibles:
- [email protected]
- [email protected]
- [email protected]