complete -c tail -s c -l bytes -x           -d 'output the last K bytes; alternatively, use -c +K to output bytes starting with the Kth of each file'
complete -c tail -s f -l follow -xa 'name descriptor'  -d 'output appended data as the file grows; -f -l follow, and --follow=descriptor are equivalent'
complete -c tail -s F                       -d 'same as --follow=name --retry'
complete -c tail -s n -l lines -x           -d 'output the last K lines, instead of the last 10; or use -n +K to output lines starting with the Kth'
complete -c tail -l max-unchanged-stats -x  -d 'with --follow=name, reopen a FILE which has not changed size after N iterations'
complete -c tail -l pid                     -d 'with -f, terminate after process ID, PID dies' -xa '(__fish_complete_pids)'
complete -c tail -s q -l quiet -l silent    -d 'never output headers giving file names'
complete -c tail -l retry                   -d 'keep trying to open a file even when it is or becomes inaccessible; useful when following by name, i.e., with --follow=name'
complete -c tail -s s -l sleep-interval -x  -d 'with -f, sleep for approximately N seconds (default 1.0) between iterations'
complete -c tail -s v -l verbose            -d 'always output headers giving file names'
complete -c tail -l help     -d 'display this help and exit'
complete -c tail -l version  -d 'output version information and exit'