Help text for importaddress referred to the first parameter as script, when in fact it's address. Calling with a script argument fails:
→ bcli -named importaddress script=2N3qhMpHK8WNo7wv87W9eHMgvGyJU1593Ei
error code: -8
error message:
Unknown named parameter script
→ bcli -named importaddress address=2N3qhMpHK8WNo7wv87W9eHMgvGyJU1593Ei
# success!