Too all of you.. I fail to see why you can't just use

/version services.network.tld

i.e:

.version services $+ $chr(46) $+ $gettok($server,$calc($numtok($server,46)-1),46) $+ $chr(46) $+ $gettok($server,$calc($numtok($server,46)) -1,46)

Then parse the reply.

You could ask services developers to add something to the version reply string if you wanted.

Like Current:
SomeServices-2.98 services.somenet.tld compileoptions

Possible Update:
SomeServices-2.98 services.somenet.tld compileoptions AVAILABLE=CS:ChanServ,NS:NickServ,MS:PRIVMSG MemoServ,BS:BotServ

Where someone desides a standard for 'identifers' - i.e. NS for Nickname Service, and the : seperates the command that should be used to send messages to it.

Either way, the idea of 005 having some token for it is crap imo. Services are by definition not something the server doesn't to tell clients it has.