When should I disable sessions?

[Tonearm]

Hi guys, my shopping cart software allows me to add entries to a directive and disables sessions when any portion of a user's UA matches any of the entries in that directive.

What I've been doing is adding almost anything that requests robots.txt to the directive. I've started to think that this might not be such a good idea. Can you guys think of any time I wouldn't want to disable sessions for a UA that has requested robots.txt in the past? That is, other than what is obviously just someone typing in :

www.mysite.com/robots.txt

Thanks!

[Receptional Andy]

Sounds reasonable to me. Maybe match your exclusions to a list of known robots? There can be no question of cloaking here, because all you are doing is trying to ensure that bots get the same content as users (AFAIK).

[Tonearm]

Actually I wasn't worried about a cloaking accusation so much as a situation where sessions might be disabled when they would need to be left in place. This wouldn't be the case with a search engine spider, but I've been noticing info here and there about robots that aren't spiders and this might need sessions? "Special viewers" and such?

[Receptional Andy]

Not sure what you mean by 'special viewers'. If you're only disabling sessions for UAs that request robots.txt, then any visitor will be OK?

[Tonearm]

So you can't think of any type of robot that would need a session?