Running spellcaster with sonnet or haiku on an some markdown docs does not seem to work; I didn't try to debug exactly what is going on, but I've included the full stdout/stderr output (with verbose logging) below.
$ spellcaster --directory $HOME/rbt/respect/reboot/documentation/docs/develop -m 10 -l claude-3-haiku-20240307 -p Reboot > output-haiku.log 2>&1
output-haiku.log