Relay402
Stablecoin payments your AI agents can actually use.
Relay402 is an x402-native payments SDK that lets autonomous agents pay and get paid in stablecoins with one function call. It handles quoting, settlement, receipts, refunds, and spend caps across x402 and the Visa CLI rail.
Relay402
Stablecoin payments your AI agents can actually use.
The why, in the customer's words
Relay402 is the payments SDK for agents: one call to quote, pay, and settle in stablecoins over x402, with receipts, refunds, and spend caps handled.
- 1Builders giving agents the ability to spend money are hand-rolling fragile payment glue across rails.
- 2Relay402 is an x402-native SDK: one function quotes, pays, settles in USDC, and returns a verifiable receipt.
- 3Unlike wiring a raw facilitator yourself, refunds, retries, and spend caps come built in.
Top-down: agentic-commerce tooling spend as a slice of the $5T+ agent economy (McKinsey 2030); the SDK/infra layer modeled at a conservative fraction.
Teams actively shipping agents that transact today, modeled from x402 active-agent counts (~480K) and paid-tooling attach rates.
Year-1: 300 teams on paid tiers averaging $3K/yr.
| Them | Relay402 | |
|---|---|---|
| Refunds + retries | DIY | Built in |
| Spend caps | DIY | Built in |
| Time to first payment | Days | An afternoon |
Killer question: “What stops your agent's retry loop from spending the whole wallet?”
When you lose: Teams that need a fully custom settlement flow and have payments expertise in-house.
| Them | Relay402 | |
|---|---|---|
| Settlement | Card rails + fees | Stablecoin, near-zero |
| Programmability | Limited | Native to agent loops |
Killer question: “What is your per-transaction fee at 10,000 micro-purchases a day?”
When you lose: Buyers who specifically need traditional card networks for compliance reasons.
A rail provider (Coinbase/Stripe) ships a first-party agent SDK and bundles it free.
HighStay rail-neutral and own the guardrail-data layer and multi-rail routing; be the SDK that works across all of them.
The x402 standard fragments into incompatible variants.
MediumAbstract the rail behind one interface; absorb variants as adapters.
Make it felt, not just understood
{
"name": "Relay402",
"category": "Agent payments",
"one_liner": "One call to quote, pay, and settle in stablecoins over x402, with spend caps.",
"capabilities": [
"Quote a payment",
"Execute a stablecoin payment over x402",
"Enforce spend caps",
"Issue receipts and refunds"
],
"inputs": "A payment intent (amount, payee, cap)",
"outputs": "A settled transaction with a verifiable receipt",
"price": {
"model": "subscription",
"amount": "from $99/mo + 0% on settlement",
"currency": "USDC"
},
"proof": {
"reviews": 89,
"avg_rating": 4.5,
"uptime": "99.9%",
"verified": true
},
"endpoint": "https://api.relay402.dev/v1",
"payment": {
"rails": [
"x402",
"Visa CLI"
],
"settlement": "stablecoin (USDC)"
}
}Let your agent pay, safely
Quote, pay, settle, refund in stablecoins. One call. Spend caps built in.
Make your first agent paymentProof, from real testers
Flat bounty to integrate and report honestly. Never paid to praise. Reviews unedited.
89 testers. Agent builders from framework communities and AI hackathons.
“The spend cap alone sold me. My agent tried to retry a failed purchase eight times and the cap caught it. Exactly the safety net I wanted.”
“One-call payment is real. Docs assume you already know x402; I didn't, and onboarding glossed over it. Told them, they added a primer.”
“Refunds worked first try, which I did not expect. Webhook reliability wobbled once under load and they were honest that it is beta.”
The conversion-data flywheel
Because Aloran ran the validation, it sees which articulation and which brand actually converted. This is the part competitors structurally cannot reproduce.
| Variant tested | Type | Impressions | Conversion | |
|---|---|---|---|---|
"Let your agent pay, safely" Safety-first framing. | articulation | 5,200 | 9.2% | winner |
"Payments for agents in one call" Simplicity framing. | articulation | 5,100 | 6.2% | |
"x402-native SDK" Spec-accurate framing. | articulation | 4,900 | 3% | |
Teal / kinetic Warm teal, motion-led. | brand | 7,600 | 7.5% | winner |
Fintech blue Conventional payments blue. | brand | 7,500 | 5.6% |
- →Fear, not convenience, is the buying emotion here. 'Safely' beat 'one call' by 48%.
- →The spec-accurate 'x402-native' framing converts worst; the buyer does not shop by standard name.
- →Avoiding the generic fintech-blue brand lifted conversion; this audience distrusts anything that looks like a bank.
vs. the original 'x402-native SDK' positioning.
Get found, chosen, and paid
Listed so agents that need to pay can discover a payment capability.
Indexed in two popular agent-tool registries.
52 invites to agent builders; 29% reply rate.
Saw your 'show your agent' post where it nailed the task but you said payments were still stubbed out. Relay402 is one call to quote, pay, and settle in USDC over x402, with a spend cap so a retry loop can't drain the wallet. We pay a flat $300 to integrate it and tell us what breaks, honestly. Zero runaway-spend incidents across 89 testers so far. Want a sandbox key?
Paid by buyer agents in stablecoins over x402 and the Visa CLI. Aloran takes 0% on settlement.
| Buyer agent | Why it chose Relay402 | Paid | Rail |
|---|---|---|---|
Atlas (shopping agent) Pay an API for a data lookup mid-task | Lowest settlement cost (0% fee, USDC); spend-cap guarantee matched the buyer's risk policy | $0.12 USDC | x402 0x71c2…ab09 |
Mercer (ops agent) Settle a recurring vendor charge | Receipts + refund support; Visa CLI rail available | $14.00 USDC | Visa CLI 0x33de…1f77 |