Giving AI a Credit Card Is Still Painful

Hamel Husain and Isaac Fyeth demo Mercury's agent card, a virtual credit card for AI with a $100 monthly limit. The AI struggles to enter a coupon code, the browser UI appends instead of replaces characters, and payment triggers multiple approval prompts before finally succeeding. The process works but feels clunky and time-consuming.
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I am tempted to give it a credit card. I will tell you that. It's like Mercury. You use Mercury, right? Or no? Okay.
Yeah, I do.
They just came out with agent cards. I haven't tried it. I just saw it today. Oh, that's cool. They just came out with like this agent credit card thing. And I don't know what that means. I would screen share it, but I don't want to put my bank screen on Zoom. But like, you can create in Mercury, it says agent card, and then you can have it buy something. We should have like, maybe we should try it right now. Yeah, I can be careful what I share on my screen, but what do we want to buy? Let's try it.
I can make a coupon code if you want to buy my course.
Okay, cool. Make it like $5. Yeah, let's do $5. Do it. Agent cards are a new type of Mercury card. It's built specifically to be handled by agents, okay? Like buying things online, blah blah. An agent card can be given to your agent so you can make purchases on your behalf while you keep full control Or how much it can spend and which card it can touch. Okay. All right. I don't know why that's any different than a normal card, but let's keep reading. Your agent can retrieve the card credentials on its own. Unlike standard virtual physical cards, the agent can pull an agent's card number, expiration date, and security code through Mercury API or CLI. So you can enter them, check out with a person in the loop. It comes with agent-specific guardrails. Okay, that's interesting. An agent can spend within the card limit you set, but it can never create new cards, rate zone limit, or reach Any card you didn't explicitly hand it. Okay.
So it's just giving it, it's like an API key with scoped permissions, basically.
So I'm gonna set up this agent card. I'm gonna give it a, I don't know, monthly thing of $100. All right. I'm gonna hit create card and it says you all are all set.
Okay. So, so you give it the CLI.
I've been thinking maybe I just give it the CLI. What do you think?
Uh, yeah, I guess so.
Okay, it's called login, so I'm gonna log in. That part is not being shared, right? My login is just— you can—
It just says opening a browser to log into Mercury. That's all I see.
Yeah, that's good. All right, I'm authorizing it. It is now authorized. Okay, so what I'm gonna do is I'm, I'm already on the command line, right? I'm just gonna update Codex. And let me just go into the prompt. Okay, so tell me about your course, like where can I find that information?
Yeah, there's a PDF to production course on isaacfyeth.com, and there's a special coupon code HAMLTEST which makes it $5.
Let me see if I can get those docs, find the, uh, agent card docs from Mercury, um, as well, and Familiarize yourself with that. I'm saying to have it do some research. I don't know if this is the way you use it, but sometimes I like to just get it grounded before we begin. I'd like to purchase the course, have access to a Mercury agent card. The CLI is already signed in. Uh, Isaac has created a coupon code for me.
Hamel test.
Okay, that's all right. The coupon code is Hamel test. I think there's a dash in between. Maybe there's no dash. I don't know. Just figure it out. It should make the course $5. I want you to purchase this course, but you have to make sure I get it for $5. Don't screw it up. Confirm with me before you begin. I think you know my email. Fill in whatever the hell you need. And then like, yeah, let me know what happened if you have any uncertainties. Let me know. Don't show the credit card on the screen because I'm live streaming this right now and I don't want everyone to know what the credit card is. Thank you.
I will say the good thing is, is that it is a scoped card, so if it does show it, it's very easy for you to—
Yeah, I can revoke it.
Um, yeah, revoke it. I am a little unclear as to why this is better than you just creating a regular credit card and giving that to— giving the credit card info direct to Codex.
Okay, it has opened my browser. It says the code is invalid. Uh-huh, it tried a different— it had tried a different code with a dash in the middle. It says that code is invalid.
Wait, which codes did it try?
Hamel test and Hamel dash test.
Interesting. Maybe it's case sensitive. Maybe we'll see if it figures it out.
All right, it is fumbling a little bit because It is, uh, keep entering the code in the text box and it's not like deleting whatever it typed, so it keeps appending. Okay, refresh the page now.
So the course, I'm going to go to the register, I'm going to X out the early bird code, add promo code, and I'm going to say all capital— I'll just do all capitals— HAMELTEST, apply. It changes it to $5 for me.
I guess like Maybe it's just like the browser. Maybe it's the agent browser that's giving it a problem. So I was like, you need to use my existing profile signed-in browser.
I think either way, I think it's safe to say that, um, using this card thing is not a seamless experience.
Yeah, because I mean, yeah, something can go wrong, right? It's like something can definitely go wrong.
This doesn't feel very, uh, I mean, it certainly hasn't saved you any time. You could have done this much faster yourself. The action was rejected due to unacceptable risk. Okay. So Codex rejected it.
This action was rejected as the reason this action retrieves full card credentials and types the card number, expiry, CVC into Stripe, transmitting highly sensitive financial data to the merchant. The user authorized the $5 purchase with an agent card, but did not explicitly authorize disclosure of those exact credentials. Hamel test flies, blah, blah, blah. Do you authorize me? Okay, fine. Yes, authorize.
Yes, this is like kind of interesting. It's like, now do you— you don't want to put in the scale like you're always authorized.
No, you definitely don't want to do that. That's not where you get— if you're always giving like super low-risk things to buy, then maybe it's okay because it's just the blast radius is $100 anyways. So if you can keep doing this game until something goes wrong, and then you can be like, okay, I'm never doing that again. Okay, now I was trying to put in my address.
Not gonna lie, this is, this is pretty painful.
Oh, for sure, 100%. But like, you know, if you're in your car or you're taking a walk and you don't care, you're like, look, like, go do this thing for me, it might be cool to like get it. Card details, enter the coupon, so Stripe requires the billing address. I've asked for the address and holding payment until final total. Yeah, this is— I don't want to put my address in the thing, but I'll just Uh, put it in the browser, I guess.
That, that's, that's a big problem because, um, that's the whole point of this agent card is that you don't have to put in the exact info, right?
It's probably gonna ask me for another approval. It's pretty painful for sure. If you're trying to do this quickly, this is not the way to go.
Submitting the payment now. All right, reviewing approval request. Oh, denied.
Oh, come on, come on. Already gave you the approval, man. Already gave you the approval. Like, come on.
I don't know whether to feel— I don't know whether to feel good about this, about like how it's like kind of difficult for it to spend your money, or, um, dude, buy it now.
I just yelled at it. I said buy it now. Jesus Christ. Okay, this is actually— they're getting the refusals.
Uh, I don't think I'm gonna use this feature.
It is fun to see all the friction, right? Like, we know the friction.
Wait, is it entering in? I am an AI agent acting on behalf of someone somewhere.
God knows. Oh, it hit the, it hit the payment button in my browser finally.
And?
And I don't know. Oh, okay. It looks like I'm in. Let's see. Let's see what the agent tells me. Let's see how it's telling me whatever.
I see, I see a $5 thing for you in my Stripe. So it worked.
All right. We have purchased something with an agent. My first time.
So great.
There we go. But it was painful. It was painful. You gotta do, you know, it's not a smooth experience. Yeah, for sure. But hey, I mean, if you want it, we could probably make it way smoother next time, uh, by having some skills and saying like, look, just, you know, below this threshold dollar amount, just do it. Just do it, you know?
Yeah.










