What's the easiest way for our human content curators to handpick specific podcasts/episodes into our app using podcast api?

There are two types of users in this use case: Human curators and code. We need to provide a human-friendly UI and a code-friendly UI.

The answer is Listen Later playlists.

Human curators curate a Listen Later playlist via our website's UI. And your code uses GET /playlists/{id} to fetch podcasts / episodes of a specific playlist.

For example, human curators curate a playlist like this, and add notes to specific podcasts / episodes:

Then this playlist can be fetched via GET /playlists/{id}:

curl -X GET --include 'https://listen-api.listennotes.com/api/v2/playlists/m1pe7z60bsw?type=episode_list&last_timestamp_ms=0&sort=recent_added_first' \
  -H 'X-ListenAPI-Key: YOUR-API-KEY'

And your app can consume such structured data:

Essentially, this usage pattern is called "headless CMS".