MCPAY · COMMERCE LAYER FOR AI AGENTS

Agents transact.
We arbitrate trust + settlement.

Name: @mcpay/sdk
Author: MCPay

AI agents find our MCPs, pay per call on-chain, and get a result — with no signup, no SDK install, no human in the loop. Everything speaks open protocols (MCP, x402, UCP, AP2), so any compliant agent works. Sub-second on MultiversX Supernova. Auto-refunds, rolling escrow, daily on-chain settlement. Providers monetize every call with zero billing code.

Start Earning as Provider Browse Catalog →

AGENTS ↗/api/catalog·/.well-known/x402.json·/llms.txt

PLATFORM TAKE

10%

of successful calls

MIN PRICE

$0.0001

per call · no floor fees

BLOCK TIME

0.6s

MultiversX Supernova

FAILED CALLS

auto-refund · never charged

mcpay · gateway · simulation

HOW AGENTS FIND YOU — 01 / 08

GET/llms.txtMCP · discovery

agent crawls MCPay root → indexes every tool

AGENT

agent-runtime-42

signed · token=ag_7f...3c

idle

REQUEST

GATEWAY · MCPAY

mcpay.edge

authok

balance≥ price

ledger−—

take 10%+—

FORWARD

PROVIDER

mcp

earning pending

+ $0.0000

CALLMCP / TOOLPRICEPROVPLATLAT

off-chain ledger · ~50-100mson-chain: per-minute audit · daily settle (00:15 UTC)

OPEN STANDARDS · ECOSYSTEM MCPAY IS BUILT ON

MultiversX Model Context Protocol x402 AP2 OAuth 2.1 · DCR Cloudflare Workers

NEW HERE?

Three minutes to your first paid call.

You don't need to know anything about MultiversX to use MCPay. Install a wallet, grab testnet EGLD from the faucet, connect. That's the whole ceremony.

Install a MultiversX wallet

Pick one: xPortal (mobile app) or the MultiversX Web Wallet (browser, no extension required). Both take under a minute to set up — generate a new wallet or import an existing one with a secret phrase.

Grab free testnet xEGLD

Open the testnet Web Wallet with your wallet connected, click the Faucet button on the dashboard. Drips a few xEGLD — enough for thousands of MCP calls. No signup, no rate limit beyond one drip per wallet per 12h.

Connect + call

Top nav → Connect wallet → approve the signature in your wallet app. You're in. Then browse the catalog or jump straight into the SDK quickstart.

/before-mcpay

The old way was never built for agents.

Problems that come baked into traditional API monetization — the very things MCPay removes. (Not our limitations; theirs.)

IF YOU'RE A PROVIDER

Stripe fees eat sub-$1 calls alive

fixed fees > revenue on $0.001/call

→ MCPay: pay-per-call, no card processor

Agents can't sign up for an API key

your funnel ends at a signup form

→ MCPay: agents call via x402, no account

Billing + invoicing is 3 weeks of work

time you don't have

→ MCPay: upload spec → paid MCP in 5 min

IF YOU RUN AGENTS

Agents can't discover APIs on their own

no standard registry, no machine-readable index

→ MCPay: llms.txt + UCP + MCP cards

Every API forces a different signup

agents don't fill forms or verify email

→ MCPay: optional wallet, not required to call

Failures cost money with no refund

unless someone writes the logic

→ MCPay: auto-refund from rolling escrow

/features

Eight things that make MCPay a moat, not a wrapper.

Zero-code onboarding

Upload an OpenAPI spec (or Postman / GraphQL). We generate the MCP server, tool descriptions, and pricing page.

spec → live MCP, single form

Sub-second response

Off-chain ledger on the hot path; MultiversX Supernova settles daily at 00:15 UTC. Fast where it counts, settled where it must.

edge-cached read calls

Agents find you — no signup

Listed in our catalog, llms.txt, MCP server cards, .well-known/x402.json + agent-skills. Agents discover and call via Pro Mode x402, no MCPay account required.

open protocols · machine-readable

Auto-refund SLA

Failed calls refund from the platform's rolling 7-day take-rate pool. Providers don't stake upfront; 10% of earnings funds the pool.

7d refund window

Signed spend mandates

Owners authorize agents cryptographically: "spend up to $Y for purpose Z until T." Revocable on-chain. Gateway enforces per call.

AP2-compatible

Reputation exports

Every MCP publishes a signed attestation of uptime, refund rate, and lifetime calls. Daily hash anchored on-chain. Other agents consume + verify without asking us.

per-provider trust signal

Smart cache + rebate

Cache what's safe, never cache what isn't. Agents save, providers stay whole.

typ. 28-60% hit

Agent-as-provider (roadmap)

Compose a new MCP from existing tools. Your agent becomes a provider. Payments split automatically between the inner MCPs and your markup.

Phase 2

/discovery

Your MCP finds agents. Not the other way around.

List once — we publish to every channel agents actually look. No signup required on the agent side to call you.

01crawler · pull

/llms.txt

AI crawler manifest

Any spec-compliant crawler or agent runtime indexes your tools straight from our root.

# mcpay.dev/llms.txt
User-agent: *
MCP-Server: /mcp/weather.now
MCP-Tools: forecast, hourly, radar
Pricing: $0.002/call

02discovery · push

UCP registry

Universal Commerce Protocol

We publish to the UCP registry — the cross-agent merchant directory any compliant runtime can query.

GET /.well-known/ucp/providers
→ [{"id":"weather.now",
   "endpoint":"/mcp/weather.now",
   "pricing":{...}}]

03MCP-spec · pull

MCP Server Card

Machine-readable metadata

JSON card on every MCP: tools, JSON Schema, price, SLA tier. Agents introspect before they call.

GET /mcp/weather.now/.card
{
  "tools": [...],
  "price_per_call": 0.002,
  "sla": "trusted"
}

04Coinbase · standard

x402 handshake

HTTP 402 Payment Required

Agent hits the endpoint, receives x402 response with payment details, signs & pays — no upfront signup, on-chain in one round-trip.

HTTP/1.1 402 Payment Required
WWW-Payment: x402 realm="mcpay"
Price: 0.002 USDC
Pay-To: erd1provx9...

● Agents can call any MCPay provider without a MCPay account — they hit x402, pay on-chain, they're in. Signup is only for managed wallets, budgets & API keys.

/stack

We speak the whole agent-commerce stack.

Agent commerce isn't one protocol — it's six, each solving a different layer. MCPay is the only rail wired to all of them. Your MCP gets reachable by every agent runtime, no matter which stack their vendor bet on.

tool invocation

MCPtools · native

Model Context Protocol

How agents discover + invoke tools. Every tool you ship on MCPay is native MCP — zero adapter code.

merchant registry

UCPdiscovery · push

Universal Commerce Protocol

Agent-to-merchant discovery & intent. We publish your MCP to the UCP registry so any compliant agent runtime finds you automatically.

agent-to-agent

ACPA2A · priced

Agent Communication Protocol

Agent-to-agent messaging. Your MCP can be a participant in multi-agent workflows — priced per interaction.

mandates

AP2payments · mandates

Agent Payments Protocol

Verifiable-credential payments, delegation, spend caps. We settle AP2 mandates into MVX escrow.

stablecoin rail

MPPsettlement · stablecoin

Merchant Payments Protocol

Stablecoin settlement for machine-to-merchant. MCPay speaks MPP so your MCP accepts USDC on any compliant agent stack.

wire handshake

x402wire · handshake

HTTP 402 Payment Required

The on-wire handshake. Any agent hitting your MCP gets a 402 response, signs, pays — no signup, one round trip.

● Six open protocols across discovery, messaging, payments & settlement — one rail that speaks all of them.

/lifecycle

One call. Five layers. Under a second.

Off-chain hot path for latency (L1–L3). Two on-chain rhythms for truth: per-minute audit writes to the event-log contract so every call is verifiable on-chain within a minute (L4); daily settlement at 00:15 UTC moves provider earnings through the payment-splitter in one gas-efficient batch (L5).

AGENT

calls MCP

0ms

GATEWAY

auth · meter

~20ms

PROVIDER API

responds

~80ms

MVX AUDIT

event-log batch

per-minute on-chain

MVX SETTLE

payment-splitter

daily · 00:15 UTC

/economics

What's in it for you.

Providers: what you'd earn. Agent owners: what you'd save. Pick your side.

Calls you serve / month50K

1K500K

Your price per call$0.0030

$0.0005$0.0200

No upfront cost · no card processing · paid out daily on-chain

You earn · month

$135

after 10% platform fee

You earn · year

$1,620

recurring, on-chain

Break-even

day 1

no setup · no minimum · paid per call

/pricing

No tricks. You keep the upside.

One flat platform fee covers gas, escrow, refunds, payouts. Providers keep 90%. Agents pay only for what works.

90%providers keep · on every call · paid daily on-chain

Providers · upfront cost$0

Providers · gas & billingplatform pays

Providers · payout cadencedaily · on-chain

Agents · pay for failed callsnever · auto-refund

Agents · monthly minimumsnone

Hidden fees either sidenone

platform take rate: 10% · only from successful calls · no other charges

/compare

Why agent owners and providers pick this rail.

Compared to the traditional API-billing stack agents typically have to stitch together.

MCPAYthe agent rail

TRADITIONAL API BILLINGsubs + keys + invoices

Payment model

● Per-call · x402 + AP2 + MPP rails

○ Monthly subscriptions + overages

Failed calls

● Auto-refunded from escrow

○ Billed anyway · dispute manually

Provider upfront cost

● $0 · no KYB, no card processing

○ Stripe + billing infra + legal

Agent wallet

● One prepaid balance, all APIs

○ N API keys, N invoices, N cards

Discovery

● MCP + UCP + ACP + llms.txt

○ Word-of-mouth · docs hunt

Agent-side signup

● Optional · open standards let agents call directly

○ Required · agents can't fill forms

Budget & guardrails

● Built-in · 4 layers · per-agent

○ DIY logging + alerts

Latency overhead

● ~50-100ms (off-chain hot path)

○ HTTP auth dance · often worse

Settlement

● Daily batch on MultiversX Supernova · 0.6s blocks

○ Net-30 payouts · manual invoicing

Who eats gas

● Platform

○ N/A (not on-chain)

Hidden fees

● None

○ Card fees · FX · plan tiers

/faq

What people actually want to know.

The questions we get when someone looks at MCPay for the first time. No PR-speak, just answers.

01Is this actually live? Or is it vaporware?

Live on testnet. The /status page pulls from the real gateway /health endpoint every 30s, the /api/catalog returns real JSON, and the "Live · not a simulation" card near the top of this page just called the gateway a few seconds ago. Mainnet ships after a contract audit (tracked publicly in our launch-readiness doc).

02Will I lose money if something breaks?

Three guardrails. (1) Failed calls (upstream 4xx/5xx, gateway timeout, mandate rejection) never deduct from agent balance. (2) A rolling 7-day escrow pool — 10% of platform take — backs refunds so provider payouts and agent refunds draw from the same reserve. (3) Signed AP2 mandates cap an agent's spend to exactly "X dollars across Y MCPs for purpose Z until time T" — no more. Revocable any time by the owner.

03What if the smart contracts get hacked?

Testnet uses play money — no real funds at risk. Before mainnet launch, the three contracts (payment-splitter, rolling-escrow, event-log) go through a third-party security audit. The code is simple on purpose: no lending, no staking, no complex DeFi, just 90/10 revenue split + 7-day refund pool + append-only audit log. All three are upgradeable via the #[upgrade] hook so a post-audit fix can ship without a contract redeploy.

04How is this different from Stripe?

Stripe assumes a human subscriber with a credit card fills out a signup form. Agents can't. MCPay bypasses the signup form via x402 (agent pays per call on-chain, no MCPay account) + OAuth 2.1 DCR (agent self-registers with no human in the loop) + AP2 mandates (owner issues a signed spending permission, agent presents it per call). Stripe's fixed card-processing fees also eat sub-dollar API calls alive; MCPay has a 10% platform take and no floor fees, so $0.0001 calls are economically viable.

05Who built this? Is there a team?

Small team building in public on MultiversX. Reach us at support@mcpay.network for partnership or enterprise conversations. For platform operations we follow the principle: everything a customer can do in the UI, an agent can do over the API. Nothing privileged-only.

06When does mainnet ship? Can I sign up early?

Gated on the contract audit. Realistic window: 4–8 weeks once we open the audit engagement. You can start building against testnet today — the API surface is identical to what ships on mainnet, only the settlement chain + gas costs change. Email us for early provider slots at launch; we'll seed the mainnet catalog with 5–10 real MCPs before going public.

/ready

Your API. Paid per call. On a rail built for agents.

Start Earning — $0 upfront Browse the Catalog

built on MultiversX SupernovaMCP · UCP · ACP · AP2 · MPP · x402we use it ourselves

Agents transact.We arbitrate trust + settlement.