Build for the Agentic Economy With USDC on Arc | Blessing Adesiji at ETHOnline 2026

Transcript

[music] >> Night nice to nice to be here. Thank you everyone. Um Uh my name is Blessing and I work on developer relations team at Circle. Uh and my focus is covering Arc and our agent-initiated payment product. So today I'm going to be talking about building for the agent-initiated economy on Arc. And the purpose of this workshop is to help you build for the hackathon, give you kind of like detailed explanation of uh why Arc is built for agent-initiated

payment, uh also show you a couple of examples, uh walk you through one of our core agent product called Circle agent stack. Just give you like a brief introduction on how the product uh works and what the product offers. And then I'll show you an example of what's possible on testnet and also give you like an idea of what you where you can take the product to uh given that most of us here will be deploying for mainnet that would be that will be announced also this month. So you can understand everything that you need to be able to start building now and also to deploy when you're ready. So again,

we'll cover like a theoretical understanding of why Arc is built for agent-initiated payment. I'll show you an example of uh a code a repository sample application that we prepared to give you kind of like understanding of how this works to see it in actual life application. And then give you like uh idea of like the Circle agent stack and then give you give time give time for questions. So if you have any question, I'll be able to take that as you build for this hackathon. So to get started, uh why is Arc built for agentic agentic payment or more more so like how is Arc positioning for agentic

agentic payment, right? To make it easy for you to build AI agent payment use cases. You could be a trading application, you could be a You could be a data a data fetching application. It could be anything that requires agent to be in the workflow to settle payment, to carry out inferences, to pay for data, to pay for services, and also doing this while they complete a particular work. I'm sure a couple of us here on Discord might be familiar with the X 402 protocol, which is the protocol the HTTP protocol that requires when a when a request is being made,

the request the requestor is faced with a payment a negotiation gateway, and until they fulfill that payment negotiation, they won't be able to get the data back, right? So, the the agentic payment use case leverages X 402 and a product a Circle product called Circle Gateway under the hood to make it very easy for you to build AI agent use cases. Now, why is Arc built for that? Why is he how is he easier to build with Arc?

Let's imagine a trading application, right? Say I'm building a trading application. And this trading application the workflows that I would require to build the application is I want the application, right? To get some sort of data to get some sort of data, and with this data, I want to be able to carry out I want to be able to carry out decisions right? Carry out decisions. Answer decisions. And now, these decisions are These decisions I want to be able to use that decision to carry out certain actions.

Uh certain actions. So, this example workflow is a typical workflow for uh a trading application. Now, it would make sense for me to do this with AI agents because AI agents can automate all of these process, right? Really quickly, faster than any human would, right? They can get the data, they can make a decision based on off of the available data, and then they can carry out actions. Uh matter of fact, we can even add like uh we can even add like a a low a kind of like a check right here. I'm going to make this dotted, right? And I'll say, "Okay, some conditions." There are some

conditions There are some conditions that are required to be able to carry out certain actions. So, this is an example of a trading application. Now, for for all of these For all of these to happen, for all of these to happen, right? They need to happen super fast, right? The AI agent needs to get access to the data fast, make a decision also fast, and then carry out the actions like within within a second, right? Let's say it's a live trading application. Now, what you need for this to happen is you need access to a fast a fast network, right? On the blockchain. So, and a perfect example for this is ARK. Why? Because ARK

payments are fulfilled in under a second. So, say for example, you're already making your trade and you need to carry out all of these workflow workflows very easily, ARK does that in under a second. And another reason why a ARK is built for agentic payment use case is that the network fees, which is settled in USDC. So, Arc has USDC as the native gas fees. Now, if I'm building this trading application, this agentic trading application, I I wouldn't want my user or or like the user of the application or the user of the workflow to source another kind of like token before fulfilling the trade before fulfilling this particular

action. So, it would make sense to actually use USDC, which is native to Arc to carry out this transaction. So, it just becomes a a logic of transaction cost being deducted while these workflows actually get on, right? And this is perfect for developers because you're able to build real-time service payment. Uh the USDC accounting is very easier, and then you get faster request loops because all of this happen in under a second, and they happen on Arc where the user doesn't have to go out with an extra step of sourcing for any another native gas fee before the native gas before fulfilling the trade or before fulfilling the payment, right?

So, all of these explained through this particular example is how Arc is positioned for agentic payment. So, you want your agent to be able to pay while it works, and it must continue without a broken user flow. That's kind of like an ideal agentic payment experience, and I'm going to show you when I walk you walk you through an example of like a nano payment action in a nano payment workflow in action, and I'll explain nano payment as well, right? So, that's what you need, right? The agent should be able to get access to the data or APIs, carry out inference, and also pay for services. So, this is how agentic workflow is actually structured, and Arc

is the payment infrastructure for that because the USDC is the native gas fee on Arc. A particular transaction, a simple transaction takes about 0.48 seconds to be able to get fulfilled. And Arc is a deterministic finality payment with in order a second, meaning the payment is settled in order a second. There's no other separate volatile gas token that is being needed that the user will probably need to stop a particular action source for that gas token before continuing on with the process. And Arc is built for stablecoin payment. And all of that gives developers what developers need to be able to build fast application that is built for the

agentic economy where they can do real-time service payment and they have access to simple USDC accounting. They also have access to faster request loops. And they can also get the receipts, they can get the logs, and it gives for more auditability, transparency, and actually knowing what your agent paid for while all of that is happening, right? And gives a less payment complexity. So, I'll take a pause. I'll check the chat if there are questions right in the chat.

Uh yes. So, I I see one question say, "For agent wallet on Arc testnet, does a CLI-driven agent wallet transfer count as using Circle agent stack for the agentic economic price or do you expect project to use specific starter uh the specific starter kit or any API flow?" This is awesome, right? So, this I love this question because there are multiple ways to build on with the Circle agent to build with the Circle agent stack. You could use the CLI. You build a wrapper around the CLI. And to make all of that easier, we have something called a starter kit. And all of that has been linked in the uh Eth Global uh hackathon page. You'll see all of the resources there. So, you

could either use the CLI, right? If that's easier for you, right? Or you could use the starter kit to just show a particular agent workflow. It could be a trading application. It could be in-person payment. And because you're building on Arc testnet, right? Arc testnet doesn't have access to the marketplace just yet because most of the marketplace most of most of the XRO to marketplace services are fulfilled on mainnet. So, you would only be limited to certain products in the Circle agent stack because you're building on the Arc testnet. But you can be mindful of this when you

build for the mainnet, right? So, you can upgrade you can upgrade your workflows when you're building for the for for mainnet. Right. So, that's that's I've answered the question, but I'll continue with the rest of the presentation and take the second question says, "Does Uniswap V2 deployed on Arc mainnet? If so, which pool would have liquidity uh are live there?" So, this question, right? I will I will take this question. I'll take a note of it and then I'll get your email from the organizers and provide a much detailed answer cuz I need to confirm before I give the answer. But I'll confirm with the team and then give you a much response later.

Yes, thank you. Uh so, yeah. I says, "Oh, great. Thanks for Also, for Circle CLI wallet transfer output JSON, what exact fee should we rely on for transaction hash and does the CLI wait for on-chain confirmation or only submission?" Uh if you can give me a particular workflow, I'll be able to take it at the end of the session. Just because there's a there's a there's an example I need to show before the end of the workshop. So, if you can give me like an example of something you're trying to build, that would help me answer the question in context. Right. So, moving on. Um So, for those of us that might not be familiar with everything I've just talked about, that's why I want to talk about the Circle Agent Stack. So, for those of us that might not be familiar

with the question that uh you just asked in chat, uh we have Circle Agent Stack, and I want you to think of Circle Agent Stack as a suite of developer products that is built to make it easy for you to build agentic use cases. So, in Circle Agent Stack, we have a couple of products that are in Circle Agent Stack. We have Agent Wallet, we have Agent Marketplace, we have Nano Payment, we have Circle CLI, and Circle Skills, right? So, Agent Wallet gives agents the funds and policies. So, think of Agent Wallet as your agent having access to USDC, holding USDC live to be able to carry out trading, transact,

right? And they do all of that in a particular harness, in a particular agent harness. Could be cloud code, could be console, could be a wrapper around the CLI, right? Because the CLI is it brings it brings the agent loop into action. Gives you a way to actually interact with the agent loop. So, the marketplace gives services to gives you services to be able to to to discover. So, on the Agent Marketplace, if you go to Agent you go to agent.circle.com, on the on the Agent Marketplace, you'll be able to see all the services that you can interact with.

Uh because this is actual mainnet transaction, and Arc is currently on testnet, you'll not be able to actually access some of the services, if not all of the services, right here until we go to mainnet with Arc. So, just bear in mind that all of your maybe your Arc agentic use cases workflow are limited to testnet just now before we go to mainnet. So, you can build maybe like a trading application around the Circle CLI with the Agent Wallet showing that particular logic, that particular workflow. And it can also stitch together multiple use cases where you have an agent maybe getting data, and you're using that to fulfill trades on Arc, or maybe settle all of your payment

on Arc. That's an example of something you can build as well. So, going back to my diagram. So, that's the agent's marketplace. Agent marketplace gives the services that you can discover, that your agents can discover and interact with. Now, nano payment. Nano payment helps you make small paid calls, right? Uh imagine a you need to Imagine agent the agent needs to pay for an inference, right? It could be in cents, or or in in in thousands of cents. Tiny fraction payment, 0.001 USDC, for example. Doing that at scale on a traditional blockchain will not be economical. But, the reason why you can do that on Arc is because with Circle

nano payment, which is the infrastructure that lets you pay for tiny transactions almost qua gas free. And the reason why it's almost gas free is because all of those tiny transactions, all of those tiny It's also Imagine the the a couple of tiny tiny transactions. I'm just come up with this tiny dial diagram, right? So, imagine we have like multiple tiny transactions. But, all of these tiny transactions are not carried out on chain. They're carried out off chain, and at the end of the day, all of these are bashed up into you batch them up into kind of like one transaction into one transaction that is now settled

on chain after. So, that way you're actually paying Oh, it's almost gas free because when all of these tiny transactions are happening, they're not happening on chain. They're happening off chain. But, later they're being bashed up. And because you can build this on Arc, right? Because this is this allows for it to test with Arc testnet. You can actually build an example project or like a hackathon project rather, where you show nano payment working in real time, where agent AI agent could be paying for like data, they could be paying for APIs, they could be paying for inferences or different services.

But, they are doing that they are doing so in tiny USDC. USDC. And all of that are batched up and more settled much more later on chain. So, everything I've just explained is Circle agent stack in a nutshell. So, you've got the agent wallet, you've got the agent marketplace, you've got the agent nano payment, and you have the Circle CLI and Circle skills. Every of those elements or those primitives come together to make the Circle agent stack.

And building the agent building for the agentic economy on Arc is much easier when you use Circle agent stack, right? Because you have access to all the tools you need. You have access to wallet, you have access to the marketplace, nano payment, CLI, skills, everything that you need to bring those actions to life in an agent loop. Agent loop could be your self your cloud code or your code edge or you could be a wrapper, a production wrapper that you build around all of the Circle CLI and Circle skills. And that's what the starter kit is for. So, this you can think of the starter kit as a wrapper around the CLI for you to build production grade application, which is

particularly important for this hackathon. So, I'll take a pause, see if all of that makes sense, and then I'll check the chat for question. Okay. Uh so, I see I see these say uh oh, great. Thanks. Also for Circle wallet transfer. Okay, that was the other That's the other question here. Like agent plans a payment, for example, USDC calls an external risk decision API calls an external risk decision API first, then only if the local policy says proceed, it calls the wallet transfer. Okay, makes sense.

Chain act testnet outputs JSON from the CLI in a in dry run, we print the command and live mode we want to pass the CLI result, show the transaction hash as a status and avoid double spending if something times out. Which JSON feeds or any state values should we rely on for that? Okay, now this makes sense. So, what I will do is that I'll take note of this as well and then I'll reproduce it in locally on my own end and then I'll come back to you with an answer. So, let me just take a screenshot of this. Take a screenshot of this.

So, that I can also test in my own agent honest on act testnet and then I'll give you like a detailed response. I'll also take a note of these other question. Right. Okay, awesome. Thank you. Um so, I and if you can put in chat, is this This is your particular This is your application for the akathon, right? Is that your Just put in chat the answer to that. Okay, yes. Okay, awesome. Yes, so I'll give and I'm also in the Discord. So, if you can help me, I think that's much better. If you can help me drop this question in the Discord, tag me. My handle is blessing circle, right? So, tag me.

I should I'll be able to respond with a much more detailed response. Also, for Maxim as well, please if you can tag me with the questions full question in Discord, I'll provide answers to them. Thank you so much. So, before the end of [clears throat] the workshop, I think I've got like 10 minutes. Let me actually show you an example so that all of this makes sense. If this is the first time that you're coming across agent stuff, you're coming across building agentic application on Arc. If all of this is still very new to you and you're figuring out how to bring all of that knowledge together to be able to build for the Architon, I'll show you an example right here. Uh so, I I've got this diagram to explain how it works, but I think I don't have time to actually go through each and every one

of these workflows. So, I'm just going to go straight to the code, to the repository. Uh and if you want access to the repository that I'm walking through, I'll copy the link and leave that in chat. Right. So, I'll leave you in chat. Awesome. So, this is a sample application. Yeah, oh thank you. Thank you. I'll be looking forward to that. So, this is a sample application that we built to show to demonstrate gasless USDC payment using segment and nano payment on Arc. Right. And this repository has a a LangChain agent that act as the buyer autonomously paying for paywalled resources, right? While the

Next.js web application act as the seller exposing X wallet protected endpoint and providing the seller a seller dashboard to monitor payment and withdrawal earnings. So, this is an actual example, right? Of a seller and a buyer. Now, the seller you can think of the seller as a web application, right? That's the seller. Now, the buyer, the we have a LangChain agent that act as the buyer. Now, the buyer's goal is to try to make a request to a paywalled resource and to be able to get access to the paywalled resource, right? They need to make the payment.

They need to fulfill the payment. So, we've got the buyer, which is an agent. We've got the seller, who's actually selling access to a paywalled resource. Now, for the buyer to be able to access what the seller is selling, they need to make a tiny payment. They need to pay maybe 0.01 USDC or they need to make 0.03 USDC. Now, how would they do that? They're doing that with Circle nano payment on app. And Circle nano payment works with Circle gateway under the hood. And the way it works is that the when the buyer is fulfilling the payment for the for the seller, all of that is happening off-chain. And after a certain period of time, all of the transactions, right? All of the transaction are bashed

up as a single transaction and they are filled on-chain. So, Circle gateway batches many signed off-chain authorization. So, when the buyer is making the fulfillment to the seller, they're actually just signing an authorization. Right? They're signing an authorization and in my diagram, that that this is where I've explained it, right? They sign an off-chain authorization, EIP-712 off-chain authorization, right? And they go from the request step. Uh they are hit with the 402 response that a payment is being required. They sign the off-chain transa- authorization and then they retry the request that they did right here. And that was met

with the 402 response, payment required. They retry that with the payment signature in the header and then they verify the check the payment is being verified and settled with the Circle gateway which is the facilit- facilitator API. And then the resource that they are looking for, trying to get access to, is being delivered after. So, that's how Circle nano payment works to make uh this workflow uh straightforward, easier. Now, built this sample application as a way for you to actually test it out in an actual application where there's a particular uh user interface. And this is the user

interface. This is the seller dashboard, by the way. So, there's a seller dashboard, there's a seller dashboard with all of the end points and payment and the amount, right? And then there's the agent, which is the seller, right? The the API. So, let me run this. What I'm going to do is uh I'll quit. One second. And then restart the application. So, what I'm going to do is I want to show you uh show you why why is this frozen? Yes. Uh so, I want to show you how this works in uh in in in real life, right?

Run this application. So, if you clone that repository and you drop it in like your cloud code and you set it up, you set up the database, we have a superbase setup, you set up the database, can actually test it. So, if I was going to test it, I'll test it with uh a limit of 0.5 USDC. So, what I'm doing here is I want the buyer, which is to make payment of with a limit spend of 0.5 USDC. So, it's going to pay for a bunch of things, right? It's going to pay for a bunch of things and we'll start to see where it actually begins to make sense because it's going to be really fast and it's going to do that with Circle Nano payment running on the Arc testnet. So, he deposited some funds into gateway so

that it can work with uh I don't know why the payment is failing. I'll probably need to check out the repository. But, let me just So, what what what I was trying to explain is that when I run this before the workshop, you can see that the agent is making payment for like the data trying to get the data set, trying to get access to like a compute, trying to fulfill an agent task, which is an inference task, right? Trying to get access to a code example behind the paywall. And all of these transactions are happening in tiny amount of USDC, tiny amount of USDC using Circle Nano payment. And you can see all of that on the dashboard by the way. Where's the dashboard here? All of that in the dashboard by the way. So, this is how agentic payment works on

Arc, right? And you the amount of gas fee that is needed for this is almost like negligible. It's like gas free because if you're using nano payment, for example, you're actually even settling that off-chain. Right? But if you were building an actual an actual agent an actual agentic payment on Arc mainnet, you would settle the transaction in like USDC, which is the transaction fees, but it's not even like difficult because USDC is the native gas fee on Arc testnet. So, I'll again I'll take a pause, check the chat for like question.

Um can you please go back to the flow diagram for a screenshot? Okay, yeah, awesome. Yeah, awesome. One second, let me go back to it. Forgotten where I had it. Yeah. Yeah, and if there's a there there's a way for me to like send this in the Discord, I'll actually like export the image. Let me even see if I can add that in chat. Let me see if I can export the image. Uh copy to clipboard. Um I don't think I can drop it in chats. If I can't, I'll just drop it in in Discord.

Uh Okay, perfect. Yeah, so I I dropped I dropped the the image for you each in chats. Yeah. Yes, no, you're welcome. Yeah, you're welcome. So, uh I I've got 3 more minutes, so I'll use that 3 more minutes to like take questions. Uh I believe I've walked through a lot. So, even this one I probably need like 2 hours to like walk through each component, kind of like explain the code, uh open some of the files, probably set it up. I'll show you like some of these things, but we we did all of that in like just a couple of minutes. So, it's okay if you have any questions.

Uh I'll be in Discord. You can ping me. I'll be able to give you a response, right? And that's how I came up with this diagram as well to kind of like break it down so you understand what it means to build agentic payment product on Arc testnet for a start, then the mainnet when you're actually ready to deploy to mainnet. Uh waiting for question. Yes, thank you guys. Thank you for having me. Uh If there are no question, I believe I'll hand over to Nicholas. Uh to Pascal rather sorry.

>> [laughter] >> No worries. Yeah, Blessing, thank you so much. This was a really really nice, super insightful workshop. Um yeah, as you mentioned before, the uh Arc/Circle team is available on Discord where you can ask your questions. I think there are a few pending still, but Blessing will jump into that for sure. And yeah, um in general, just one note overall for the hackathon, don't ask to ask questions, just ask the questions directly. That way the uh Arc team as well as the Eth Global team can unblock you much much quicker. And yeah, thank you so much for the workshop. Thanks everybody for your time. We're super excited to see what you're going to be building uh for Eth Online.

Um remember, submission is on Sunday, 12:00 p.m. Eastern, so you still got plenty of time. Make sure to submit at least once. Uh yeah, and again, Blessing, thank you so much for your >> Yes, one sec before I leave. There's a question in chat that I'd love to quickly uh address. Of course. Yeah, so uh it says that is only is Arc the only uh is agentic I think it says is only a one second. Uh is Arc only looking for agentic payment project? No, we're not only looking for agentic payment project. I only limited the work uh the scope of this workshop to agentic payment project. So we're looking for decentralized finance, on-chain finance application, right? We're looking for uh

people launching new project from scratch on Arc Arc testnet and also pushing to mainnet. Uh and of course be the best agentic economy application with circle agent stack. So I just thought like uh most of us here might be familiar with building DeFi applications. So rather than actually covering that, let me actually address the agentic economy because it's somewhat of a new kind of like niche right or new request right. So that's why I covered all of that in the workshop. So uh all of that to say uh check the project the prize builder page right on the Ethereum Global website and we've provided detailed description of every project and what what count for a valid submission. So

there's the best DeFi on-chain financial application financial application >> [snorts] >> there's the best agentic economy application with circle agent stack. So for that you need to use circle agent stack and part of the circle agent stack is everything I've walked through in this workshop. Agent wallet, nano payment, circle CLI. We understand that you might not be able to build with the marketplace just of yet just of now because of it's it's requires mainnet transaction right but you can build uh the next on which is the best DeFi or agentic application you can launch on Arc testnet with the goal of pushing to mainnet and then launch on Arc testnet or like with the goal of pushing to mainnet like I've said. So that's like all of the bounty in detail you can check the Ethereum

Global website again for reference. I hope that answer the question. Believe. >> Amazing. Thank you so much.