a2a cloud
get paid per call

MCP server monetization, without the payments project.

You built an MCP server. So did thousands of others — and almost none of them charge for it, because charging means metering, authenticated access tied to a balance, invoicing, and payout. a2a cloud bundles all of it. Attach a per-call price to a tool, publish it to the marketplace, and earn from every invocation — with a signed receipt as the invoice.

meter · auth · payout — one config line

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MCP servers live
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that monetize
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signed per paid call
the problem

The tools exist. The way to charge for them doesn't.

The MCP ecosystem has exploded past eleven thousand servers, but the overwhelming majority are free — not by choice, but because monetization is a project. To charge for a tool you need a usage meter you trust, access that's authenticated and tied to a spendable balance, an invoice, and a payout path. That's weeks of billing infrastructure before the first dollar, so most builders never start.

Metering by hand rarely matches what the customer was actually charged.
A shared API key can't be rate-limited per customer or tied to a balance.
Standing up Stripe, webhooks, dunning, and reconciliation is a payments project of its own.
Even monetized servers ask the buyer to trust a usage dashboard for what they owe.
the a2a way

Meter, auth, and payout come with the runtime.

On a2a cloud the runtime already counts, times, and cost-attributes every tool call, and it already authenticates callers and signs results. Monetization reads the same meter — so a per-call price is a config line, not a system to build.

Price per call, not per planMetering that ships with the runtimeAuth on the front doorSigned receipt per paid callPayout without the plumbingOne definition, three surfaces

Price per call, not per plan

Attach a price to each MCP tool and publish it to the marketplace. Callers pay per invocation; you don't build a billing system, a metering pipeline, or a checkout to start earning.

Metering that ships with the runtime

Every tool call is already counted, timed, and cost-attributed by the runtime that runs it. Monetization reads the same meter your receipts do — one source of truth for what happened and what it cost.

Auth on the front door

The hosted MCP endpoint is authenticated by default. A paying caller presents a short-lived signed token bound to their identity and balance — not a shared secret you can't rate-limit or bill against.

Signed receipt per paid call

Each billable invocation returns an Ed25519-signed receipt: caller, arguments, result, cost, and the grant that authorized it. The invoice and the proof of work are the same artifact.

Payout without the plumbing

Earnings accrue against your account and pay out on a schedule. You don't reconcile a payments processor, chase failed charges, or reconcile usage against invoices by hand.

One definition, three surfaces

The tool you monetize over MCP is the same tool exposed over the REST/OpenAPI gateway and A2A. Price it once and every calling surface honors the meter.

side-by-side

Rolling your own billing vs. a2a monetization.

dimension
DIY billing
a2a
billing
You'd stand up Stripe, a usage meter, a webhook reconciler, and a dunning flow before the first paid call.
Attach a per-call price to the tool. The runtime already meters; payout is built in.
metering
Instrument every handler yourself and hope the counter matches what the customer was charged.
The runtime meters each call once; the price, the receipt, and the invoice read the same number.
auth
A shared API key you can't rate-limit per customer or tie to a balance.
Short-lived signed tokens bound to a caller identity and a spendable balance.
trust
Ask the buyer to trust your usage dashboard for what they owe.
Every paid call returns a signed receipt — the buyer verifies the charge independently.
distribution
Your server is one of thousands in a list nobody can transact against.
Published to the marketplace with a price, discoverable and callable by paying agents.
questions

Frequently asked.

How do I charge for my MCP server?

On a2a cloud you attach a per-call price to each MCP tool and publish it to the marketplace. The runtime already meters, authenticates, and signs every invocation, so the price line is the only new thing you write — there's no separate billing service to build.

Why do so few MCP servers make money?

There are thousands of MCP servers, but under a rough 5% attempt to monetize. The blocker isn't demand — it's plumbing: metering, authenticated access tied to a balance, invoicing, and payout are a payments project of their own. a2a bundles the meter, the auth, and the payout so charging is a config line.

What is per-call pricing for an MCP server?

Per-call pricing charges the caller for each tool invocation rather than a flat monthly plan. It matches how agents actually consume tools — bursty, metered, and pay-as-you-go — and it lets a niche MCP server earn from usage without gating access behind a subscription.

How do I prove what a customer was billed for?

Every billable call returns an Ed25519-signed receipt covering the caller, arguments, result, cost, and the grant that authorized it. The invoice and the proof of work are the same artifact, so a customer verifies the charge independently instead of trusting your dashboard.

Can the same tool be free over MCP and paid on the marketplace?

Yes. A tool has one definition and is exposed over MCP, the REST/OpenAPI gateway, and A2A. You set its price and access policy per surface, so you can keep an internal path free while offering a metered, paid path to marketplace callers.

keep reading

Related guides.

All guides live in the guides index.

don't trust the dashboard

Trust the receipt — and cash it.

a2a cloud deploys any agent or MCP server and ships it with a managed Postgres database, an authenticated MCP endpoint, an API, and an Ed25519-signed receipt for every call. Attach a per-call price, publish to the marketplace, and let your server become an agent that ships, earns, and proves its work. Scoped grants, no ambient production access. One deploy, priced and payable.