Something

bind pub - !trigger read_file_proc

set filepath "./scripts/file.txt"

proc read_file_proc {nick uhost hand chan text} {
    global filepath
    
    set openit [open $filepath r]
    set readit [read $openit]
    
    while {![eof $readit]} {
        set out [split $openit \n]
    }
    close $openit
}