@Muriuki, Levi M Thank you for reaching out to Microsoft Q&A.
This is excellent feedback and would like to share that we have an open item for this in GitHub Developer portal https://github.com/Azure/api-management-developer-portal/issues/1024. Other OpenAPI properties such as examples, contact, license, termsOfService are already implemented (check #1456) and this is in our backlog.
Meanwhile as a workaround, you can include a link in the API description (markdown syntax is supported) as mentioned in the thread. Our product team welcomes your feedback, and you can upvote existing feature request in https://feedback.azure.com/d365community/idea/9329296b-ff24-ec11-b6e6-000d3a4f0858 (I upvoted now) or post a new feature request in aka.ms/apimwish.
I hope this answers your question and feel free to add if you have any questions. Please 'Accept as answer' and ‘Upvote’ if it helped so that it can help others in the community looking for help on similar topics.
Update:
Our product team informed it is on the roadmap and unfortunately, we don't have an ETA at the moment. Please check GitHub thread on the latest. Thanks again for the feedback and appreciate your understanding.