If you need an agenda for a meeting, then it covers too many things. The idea of an agenda is based on some assumptions that are not true:
• We can not estimate and predict how long a certain topic will need to be discussed. Of course, you can choose to limit the time for a discussion but giving someone ten to fifteen minutes to present and then make a decision on something, either shows that the topic is so simple that you didn’t need to discuss it, or that you did not give it enough time.
• Humans can not switch from topic to topic and be expected to be focused, creative and good decision makers at the same time.
• If you fill up an hour with six ten minute discussions or four fifteen minute discussions, then you will not have time for the last couple of topics.

Instead, find what you need to discuss and set up a meeting to focus on just that. Clearly define a goal of the meeting, what you want as output from the meeting, who should show up, and preparation material.