What is an agentic payment?

An agentic payment is a financial transaction initiated and completed by an AI agent or software process — not directly by a human. The human sets a goal and a budget; the agent handles payment decisions as it operates.

Why can't agents just use credit cards?

Cards require a billing account, human-authenticated setup, and do not settle in real time. An agent needing to pay for thousands of API calls per hour, at fractions of a cent each, cannot run through a card network designed for human merchants. Stablecoins on programmable chains settle in seconds for less than a cent per transaction.

HTTP 402 is a status code originally defined in 1991 and reserved for future use. Both x402 and MPP revive it as the payment challenge signal: a server returns 402 to tell a client that access requires payment, along with the price and accepted currency.

Is agentic payments the same as DeFi?

No. DeFi refers to decentralised financial protocols for lending, trading, and yield. Agentic payments are about AI agents paying for services — compute, data, APIs — as they run. They can use DeFi rails or a purpose-built protocol like MPP.

How do MPP and x402 differ?

x402 is a per-request HTTP payment protocol: each API call can carry its own payment. MPP adds a sessions layer on top, collapsing many micropayments into two on-chain transactions regardless of how many intermediate calls are made. MPP is built on Tempo; x402 runs primarily on Base and Solana.

What are agentic payments? How AI agents pay with stablecoins

An AI agent that books travel, manages a software pipeline, or orchestrates research tasks will need to pay for things: API calls, compute time, data feeds, storage. The human who deployed the agent cannot approve each charge individually — the whole point is that the agent acts autonomously. Agentic payments are the financial layer that lets software spend money on behalf of the humans who set it in motion.

The answer the market has converged on is stablecoins — dollar-pegged tokens on programmable blockchains — combined with a new class of payment protocols designed for machine-speed, machine-volume transactions.

Why traditional payment rails don't work for agents

Every existing payment method assumes a human is present at the point of authorization. A credit card needs a billing account tied to a name and an address. An ACH transfer requires bank credentials set up in advance, and settles in one to three business days. A wire is manual. Even Stripe's API requires a merchant account, a webhook integration, and a human who agreed to terms of service.

An AI agent that needs to pay for a hundred API calls per minute, each priced at $0.001, cannot run through any of those systems. The per-transaction overhead alone — in setup, latency, or fees — would exceed the value being transacted.

Stablecoins dissolve those constraints. A stablecoin wallet is software. It can be provisioned programmatically, funded in seconds, and used to sign a payment transaction without any human in the loop. Settlement is final in under a second on a purpose-built chain. Fees are fractions of a cent. There is no merchant account to open and no statement period to wait for.

The protocols that have emerged

Two open standards are competing to be the standard for how agents pay.

Coinbase's x402 launched in May 2025 and moved to neutral governance under the Linux Foundation in April 2026, backed by Circle, Google, Microsoft, Stripe, and Visa. It revives the HTTP 402 Payment Required status code as a machine-readable payment challenge. When a client requests a resource from an x402-enabled API, the server can return a 402 response carrying a price and accepted stablecoin. The client pays and retries — the whole exchange fits inside a single HTTP request cycle. x402 runs primarily on Base and Solana, processed over 119 million transactions on Base by March 2026, and charges no protocol fees.

Tempo's Machine Payments Protocol (MPP) is co-authored by Stripe and Tempo and launched with Tempo's mainnet on March 18, 2026. MPP uses the same HTTP 402 foundation but adds a sessions layer that addresses the on-chain cost problem for high-frequency micropayments: MPP Sessions collapse any number of intermediate charges into exactly two on-chain transactions — an open and a settle — regardless of how many API calls the agent makes in between. The intermediate charges are settled as cryptographically signed off-chain vouchers. MPP is native to the Tempo chain and also supports cards via Stripe and Bitcoin via Lightning Network.

What an agentic payment flow looks like

Here is a concrete example. An AI agent tasked with analysing a dataset calls a data-enrichment API:

The agent sends its HTTP request.
The API returns 402 Payment Required with a price of $0.005 in USDC.
The agent — holding a funded stablecoin wallet — signs a payment and resends the request.
The API verifies the payment and returns the data.

If the agent is running an MPP Session, step 3 involves signing an off-chain voucher rather than submitting an on-chain transaction. The cumulative voucher amount updates with each call. When the session closes — when the agent's task is done — the server submits the final voucher on-chain to settle. The client pays gas costs on exactly two transactions, not thousands.

What services agents can pay for

The MPP Payments Directory at mpp.dev launched with over 100 services at Tempo's mainnet — spanning model providers, developer infrastructure, compute platforms, and data services. x402 enables a comparable range of API monetisation patterns across its supported networks.

The categories where agentic payments are already active include:

AI model inference — paying per token to call a language model
Data APIs — per-query pricing for analytics, enrichment, or search
Compute — GPU time or cloud function invocations
Storage and CDN — per-request access to cached or stored content

The open question: who holds the wallet?

Agentic payments require that the agent hold — or have access to — a funded stablecoin wallet. In practice this means the agent's operator provisions a wallet, sets a spending limit, and monitors the balance. This is a new operational discipline: treasury management for software, not humans.

Both x402 and MPP are designed to work with any ERC-20 wallet. The question of who custodies the keys, how spending limits are enforced, and how operators audit what their agents spent is an active area of tooling development as of mid-2026.

The bottom line

Agentic payments are not a future concept. Both x402 (100M+ transactions by Q1 2026) and MPP (live with major financial institution validators) are in production. The underlying logic is straightforward: AI agents that act autonomously need a payment method that is itself autonomous — programmable, instant-settling, and sized for fractions of a cent. Stablecoins on purpose-built chains provide exactly that. For the technical comparison of the two leading protocols, see x402 vs MPP.