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eBay explicitly bans AI "buy for me" agents in user agreement update

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Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#171

Post by mort96 »

less_less wrote: post #152
mort96 wrote: post #137

Earlier quoted context omitted.

I don't understand this line of reasoning. I don't do auctions, but if I did, it would be because I want that item. When I want something, I never have an absolute hard price ceiling; if I'm willing to pay $10000, I'm willing to pay $10000.01. I can't imagine anyone who would be happy to pay $X for an item but not $X + $0.01. Like, if I'm at a store and an item costs $500, and I bring it to the checkout and the cashi…

It's not supposed to be some red line absolute max price, but rather "how much is this item worth to you?" You set that as your max bid price. If you get it at auction for less than that, you got a good deal, but if you buy it for more, you got a bad deal. If someone outbids you, then maybe it was worth it to them, but you (supposedly) would not have wanted to buy the item for that much, and would rather use your mon…

The logic of "you shouldn't ever need to snipe, just bid your max price" only works if we assume that the max price is a red line though. If I "value something" at $5000 (as in I want to buy it at $5000), and I bid $5000, and someone bids $5000.01, I would probably be happy if I sniped them and got the item for $5000.02.

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#172

Post by mort96 »

thornewolf wrote: post #151
mort96 wrote: post #137

Earlier quoted context omitted.

I don't understand this line of reasoning. I don't do auctions, but if I did, it would be because I want that item. When I want something, I never have an absolute hard price ceiling; if I'm willing to pay $10000, I'm willing to pay $10000.01. I can't imagine anyone who would be happy to pay $X for an item but not $X + $0.01. Like, if I'm at a store and an item costs $500, and I bring it to the checkout and the cashi…

it's because this argument of "what is $0.01 more?" can be extended forever, implying you are willing to pay an infinite amount of money for anything. since we know this is silly, we try to understand what our "real" maximum is. this is difficult to do for exactly the reasons you mention in your comment! surely $0.01 is negligible! there is a tension here. and so, absolute max price is not a fantasy - the world would…

It can be extended forever in theory, and sure, that is an interesting philosophical discussion, but it isn't in practice. We're discussing sniping. That means you make the choice once: do I send in a last-second bid that's $.01 more than my "max price", or do I not?

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#173

Post by bayesnet »

cornholio wrote: post #159
cge wrote: post #124

Earlier quoted context omitted.

In my experience, most purely online auctions, other than eBay, do work that way. Numerous auction houses, for example, including essentially all the major ones, have their auctions online now: when they are hybrid, that involves online live bidding where an online bid will cause the auctioneer in the room to keep the lot open for more bids; when they are "timed" or "online only", times are extended in some way on bi…

An alternative to ever extending the deadline is a Dutch auction model, where a bid consists of the maximum price you are willing to pay. It's a bit like integrating the snipping bot in eBay and allowing everyone to use it on fair terms. For example, suppose the current price is $1 and the current winner is someone who bid $2 as their maximum bid ceiling. If I bid a $3 maximum, then I become the winner at a price of…

This is exactly how eBay bidding works now. Sniping still works because your satisfaction with the outcome of an auction isn’t just determined by “I got the item below my price ceiling” but by _how much_ below my price ceiling I got the item.

Early bids make you commit to matching other bidders’ exploratory bids. You lose out on the (naive) dream of a “great deal”. Sniping (without paid-for bot assistance) is a costless way of not revealing your ceiling until the last moment (and it commits you to actually sticking to your ceiling because there isn’t time to rebid later).

If everyone bid rationally, this wouldn’t matter, but it’s very easy to convince yourself that you can stomach bidding just a little more than your ceiling just to win the item. This cuts two ways: last-minute bids prevent this behavior from others while also stopping it in yourself.

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#174

Post by technothrasher »

mpeg wrote: post #161
cornholio wrote: post #159

Earlier quoted context omitted.

An alternative to ever extending the deadline is a Dutch auction model, where a bid consists of the maximum price you are willing to pay. It's a bit like integrating the snipping bot in eBay and allowing everyone to use it on fair terms. For example, suppose the current price is $1 and the current winner is someone who bid $2 as their maximum bid ceiling. If I bid a $3 maximum, then I become the winner at a price of…

Unless I’m missing something this is exactly how eBay works. You set a max bid and then it auto bids up to that amount so you can’t get sniped unless they bid higher than your max. Not that this is perfect either, often it means you can push other people’s bids up to their max even though you have no intention of buying the item. I’ve seen it as a seller and felt bad for the buyers

Yes, almost all online auction sites (or even offline absentee bidding) work this way. You set your maximum price and the auction house bids for you. However, in any case, bidding early gives other bidders information on how much you're willing to bid and allows them to nibble their way up to your max. So bidding late is always advantageous, even when you're setting a max bid.

I've never quite understood why people get so upset about sniping on eBay. Anybody can snipe. That's just the best play. Any time I want to bid on something on eBay, I just set my max bid on the sniping tool instead of on eBay, and then forget about it.

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#175

Post by retsibsi »

mort96 wrote: post #170
retsibsi wrote: post #169

Earlier quoted context omitted.

Your max price should be the price such that you're indifferent between buying the item at that price and not buying it at all. At a shop, usually you're paying less than the maximum you'd be willing to pay, because the shop's prices are fixed and it would be a big coincidence if the price they set happened to match your max price exactly.[1] So even if we model you as homo economicus, it's normal that you're almost…

I don't see why I would buy something if I'm indifferent to whether I buy the thing.

So it should be the highest price such that you're not indifferent, you marginally prefer to buy it. The point is that you're right at the threshold where it's just barely worth it to you.

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#176

Post by mort96 »

retsibsi wrote: post #175
mort96 wrote: post #170

Earlier quoted context omitted.

I don't see why I would buy something if I'm indifferent to whether I buy the thing.

So it should be the highest price such that you're not indifferent, you marginally prefer to buy it. The point is that you're right at the threshold where it's just barely worth it to you.

The gap between total indifference and wanting something bad enough to bid on it is always going to be more than $.01.

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#177

Post by darkxanthos »

__jonas wrote: post #166

Interesting, I’m not big on AI but I have thought often it would be nice to have an ‘agent’ that monitors ebay or other classifieds sites for items based on a natural language description. Something like “I want an old mini PC to use as a home server, it should have roughly these specs and cost under this amount”, and then an LLM would run some searches every day, parse the results and send me a message if something…

The purchasing itself can important for it to jump on a great price. Maybe it finds what you're looking for at 1a while you're sleeping for example. Also if this were a business and you were going to resell it the AI could also create the listing as soon as the item is purchased.

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#178

Post by retsibsi »

mort96 wrote: post #176
retsibsi wrote: post #175

Earlier quoted context omitted.

So it should be the highest price such that you're not indifferent, you marginally prefer to buy it. The point is that you're right at the threshold where it's just barely worth it to you.

The gap between total indifference and wanting something bad enough to bid on it is always going to be more than $.01.

I reckon that's empirically false. Shops set prices like $499.99 for a reason.

(And it has to be theoretically false, otherwise $X is equivalent to $X + $0.01 for all X, and so if you'd buy something at 1c you'd buy it for the contents of your bank account.)

If you still dispute this, you need to try to explain how a larger price difference can affect your decision. If you'd happily place a $1 bid, and you'd definitely not place a $100 bid, and a 1c difference could never deter you from placing a bid, then... well, how is that possible?

Re: eBay explicitly bans AI "buy for me" agents in user agreement update

#180

Post by MarginalGainz »

This ban isn't about 'fairness' or bot protection; it's about protecting the Impression Funnel.

Marketplaces like eBay are designed to monetize 'Wandering Attention'—sponsored listings, 'customers also bought', and sidebar ads.

An AI Agent represents 'Laser Focused Attention'. It executes a transaction with zero wandering. It effectively turns the marketplace into a commoditized backend database / dumb pipe.

From a Growth/Unit Economics perspective, an AI Agent is a nightmare customer. It has zero probability of impulse buying and generates zero ad revenue. They are banning them to save their business model, not their inventory.

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