reel info

reel info [--json] <cast>

Prints the size, duration, events, marks, and effects.

$ reel info public/casts/cli-tour.cast
title        tea shop
size         72x16
duration     6.877s
events       3 annotation · 20 input · 8 mark · 46 output
marks        1.089s	browse:start
             1.711s	filter:start
             2.474s	filter:typed
             2.785s	filter:done
             3.096s	brew:start
             4.314s	brew:done
             6.816s	brew:toasted
             6.877s	tape:end
annotations  3 reel.query

Use it to find the labels of a recording's marks, for --between, --pause-at, and ?marks=.