I usually end up piping the result to a file so I can see it and edit if I need to and cat | pbcopy the file contents to the clipboard and save it in 1password.

I usually end up piping the result to a file so I can see it and edit if I need to and cat | pbcopy the file contents to the clipboard and save it in 1password. After that, 1password either fills in the password for me or copying it is just a button click. The main issue I face is that some web sites will either not allow passwords longer than a certain length or will only allow some special characters.