My organization encourages (doesn't require) using a specific tech tool for 1-on-1 meetings. This tool allows us to share agendas, take notes, and track progress.
However, I'm hesitant about sharing my own agenda with my directs beforehand. I also don't see much value in my directs sharing their agendas with me prior to our meetings. This leaves the tool primarily for documenting notes after the meeting.
My directs aren't very enthusiastic about using the tool, so I end up being the main user. I take detailed notes during our meetings and then manually input them into the tool. This makes the notes accessible to both of us, but I'm wondering if this is the most effective approach.
Should I continue to share my meeting notes with my directs through this tool, or should I keep my hand written notes to myself?
I'm interested to hear other managers' experiences and perspectives on this topic.

Use what works
If it's not an organizational requirement, consider not using the tool. You can also ask others in your org what they have found most effective and why. Who knows, you might find a use case that makes it worth your while.
Sidenote: many orgs have a clean desk policy so that people working from home are not permitted to keep paper documentation (or have very strict guidelines on protecting it when not in use). Make sure you are following both the policy and the intent behind it if that applies.
Two sets of books
One option is to use the official tool to keep an official record, perhaps somewhat vague, and then keep your actual notes for yourself. E.g., the official entry could be something like "Preparation for Monday's event" and then your own notes could include that you gave negative feedback to your direct for poor preparation for Monday's event, what your direct said in response, and some side observations that you don't want to share with anyone. Then if the company does some sort of audit of your use of the tool, you can always point to your entry in the tool - "It says right here that we discussed preparation for Monday's event."