Cookie persistence via iRule

Hm, I tried adding in some of the optional parameters (anything beyond 'persist cookie') as mentioned on that page, but still have the same issue.

Note: Items marked with  are meant to be replaced with a value. Arguments bracketed by [ ] are used to note they are optional. They should not be confused with Tcl command evaluation.

persist simple [] []       
persist source_addr [] []       
persist sticky [] []       
persist dest_addr [] []       
persist ssl []       
persist msrdp []
persist cookie [insert [] [] |
                rewrite [] [] |
                passive [] |
                hash  [ { []} []] ]
persist uie  []       
persist hash  []
persist carp 
persist none

   = The timeout in seconds.

So using this still throws the same error:

when HTTP_REQUEST {
        if { ([HTTP::path] contains "/xyz/") } { persist cookie insert BIGIP 0 }
    }