Endpoint for searching within playlist?

[A-a-l-l-e-e-x-x]

I would like to search for items not within Spotify's global universe of items, but rather only within the context of a given playlist.

While I could implement a search myself if I had access to all items of a playlist at once, it would require me to first load those items -- But for example, my own playlists include over thousands of songs, which means I would have to send a LOT of requests to only load the playlist, even though Spotify could just return me filtered search results from their side...

It doesn't seem like such an endpoint exists, though. Is it perhaps planned? What would be my alternative?