Ok thanks for the info, I have found the data, but disappointed to see that there is nothing that is human readable.
Since my initial post, I have found this forum post.
Export everything with one click.
I share the concern of others in this post, in wanting to get my information out of Agenda in a human readable form.
For myself I would need Mac OS folder(s) of markdown files.
One file for each note and to also include any files embedded within each note, i.e. png, gif, pdf, as standalone files.
And to be able to do this as a one click operation.