x402 is an open standard from Coinbase that turns the HTTP 402 'Payment Required' status code into an active payment protocol. When an agent calls a x402-enabled API, the server responds with 402 plus a payment challenge (amount, recipient, chain). The agent sends a USDC payment on Base or another supported chain, retries the request with the payment receipt, and the server returns the data. No API key, no signup, no subscription.

Why does x402 matter for AI agents?

Agents can autonomously discover and pay for APIs without human intervention. An agent that needs a market data lookup can call an x402-enabled endpoint, pay from its wallet, and get the answer — without the user pre-funding an account or sharing API keys. This is the closest thing to true 'machine-money' on the web. Current crypto-data examples include CoinGecko's experimental x402 endpoints, Alchemy's x402 wallet-authenticated agent gateway, and CoinMarketCap's x402 MCP endpoint.

Does Hive support x402?

Hive's current pricing is credit-based with API-key authentication. We are evaluating x402 / MPP (Tempo's Multi-Path Protocol) support for a future release. If your agent's economics depend on pay-per-call settlement with no card or subscription, use a provider with a published x402 surface for that specific flow. Hive's edge is cross-provider scope plus task toolsets, prompts, and stateful monitoring, which the credit model supports more cost-effectively at scale.

x402 vs MPP vs ACP — what's the difference?

x402 (Coinbase) uses HTTP 402 + USDC for synchronous pay-per-request. MPP (Tempo's Multi-Path Protocol) is a more flexible payment-routing standard supporting multiple chains and tokens. ACP (Virtuals' Agent Commerce Protocol) is for agent-to-agent commerce — agents paying agents for services. Together with UCP, TAP, L402, and MCP, these form the 2026 'agent rails' — the payment standards that let agents transact autonomously.

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What is x402?

Written by Hive Intelligence, Product docsLast updated May 31, 2026

x402 is Coinbase's open standard for stablecoin pay-per-request payments over HTTP — repurposing the dormant HTTP 402 "Payment Required" status code into an active payment protocol.

The flow:

An agent calls an API endpoint (any URL)
The server responds with HTTP 402 Payment Required plus a payment challenge (amount in USDC, recipient address, chain)
The agent's wallet sends the USDC payment
The agent retries the request with the payment receipt as a header
The server validates the payment and returns the data

No account creation, no API key, no subscription. The agent just pays for what it uses, atomically.

Why x402 matters

x402 is the closest thing to "machine-money" on the public web. An AI agent with a wallet can autonomously discover and pay for APIs without any human intervention — no manual signup, no card, no key escrow.

The 2026 agent-payments stack typically includes several complementary standards:

x402 (Coinbase) — synchronous HTTP pay-per-request with USDC
MPP (Tempo) — multi-chain multi-token routing for payment flexibility
ACP (Virtuals) — agent-to-agent commerce: agents paying agents for services
UCP, TAP, L402 — adjacent payment-rail standards
MCP — the protocol agents speak to discover what's available

Current crypto-data examples include CoinGecko's experimental x402 endpoints, Alchemy's x402 wallet-authenticated agent gateway, and CoinMarketCap's x402 MCP endpoint. Hive's current pricing is credit-based; x402 / MPP support is on the evaluation list.

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Why x402 matters

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