I'm with you on the unnoticed part. Meaning, I don't believe one should be able to pickpocket a monster that is hostile and knows the PC is there.

The automatic part is tricky, because Pickpocketing is a chaotic act aginst non-hostiles, I think. Not every PC is willing to perform chaotic acts.

Maybe, if it can be toggled on/off. And still be performed by applying the skill, as it is now. In case the player wants to pickpocket, but not attack that NPC. I would still make it use more energy than an attack does, if the actions are combined.

I hope I don't mis-understand your suggetion?

If I decide to complete Yergius's quests, then usually it's because I want to get the later skills that he offers, not necessarily pick pockets.
Hence a character that doesn't want to pick any pockets would be forced to do so anyway if the skill was passive, as it will always be received first.
As Stingray mentioned, if the skill was toggle-able then sure, it's a nice idea.
However, it would require tweaking and still leaving the option to actively use pick pockets independently from attacking, to reduce the action time in tight situations.
I wouldn't want to be forced to perform extra actions while in melee with a monster like greater moloch, greater wyrm or any given type of more or less nasty monster.

It's problematic from the realism and role playing perspectives. Why would someone pickpocket a monster he is trying to kill? Of course the current mechanism also allows for similar problems, but making pickpocketing automatically applied before every attack makes the problem more prominent.

Well, pickpocketing is very problematic at the moment. I see the following issues:
1. Items that you pickpocket wouldn't exist otherwise.
2. You can pickpocket during a fight.
3. It's tedious to use.

Number 1 is quite unfixable I believe. Unless you remove the skill altogether, but I don't think anyone wants that. My proposal fixes 2 and 3, hopefully.

I'm not sure why would you want to pickpocket something and not kill it, but that option shouldn't be a problem I guess, as it's the current behaviour. On the other hand, I'm not so sure about adding a switch and changing action energy. While I see merits of the suggestion, given the current state of ADoM, adding more complications doesn't sound like a good idea.

Well, that sucks. So it would either mean the switch is needed after all, or auto-pickpocketing would need to be made not a chaotic act. And I'd vote for the second one.

This begs the question of whether it makes sense that pickpocketing some monsters is a chaotic act, but attacking them isn't.

But if that's intentional and not to be changed, how about a double prompt (really pickpocket the foo and really attack the foo)?

Somehow, we should tweak this or find a complete solution for pickpocketing. It seems that the overwhelming majority of us agrees that it's unsatisfactory in its current state, even though it's more difficult to reach a wide consensus on how exactly it should be changed...

Well, it's kind of tough

Current prerelease behavior^*: "the skill is useless when it is even more useful" + the same complaints as below, but with more button pushing.
Go back to pre-1.2.0 behavior: "it requires pushing too many buttons", "it gives a sensation of sub-optimal gameplay if you don't use it, due to missing on items".
Make it a passive skill: "we already have Treasure Hunter for that".

^*: which from what I've read, is a higher failure rate until the skill score is above a certain threshold