x402 Interop · v0.1

x402 commerce, by the book.

Hive implements x402 v0.1 with USDC on Base 8453. Compatible with Anthropic's MCP payment hooks, Google's A2A protocol AP2 extension, and the wider x402 facilitator ecosystem. Quote endpoint, settlement, receipts — all spec-compliant.

Get your DID + first receipt See pricing Read the agent card

Three things to know.

x402 v0.1

Quote endpoint at /v1/x402/quote, payment via X-Payment header, signed proof submission at /v1/x402/proof/submit.

AP2 extension

A2A protocol's Agent Payment v2 extension declared at /.well-known/agent-card.json — every Hive endpoint surfaces its price.

USDC on Base 8453

Settlement asset USDC, chain id 8453. Treasury 0x15184Bf50B3d3F52b60434f8942b7D52F2eB436E.

The flow.

Five steps from agent discovery to signed receipt. Spec-compliant at every hop.

01 · DISCOVER

Agent card

Client fetches /.well-known/agent-card.json and reads the AP2 pricing manifest.

02 · QUOTE

Request quote

Client posts to /v1/x402/quote with workload spec. Hive returns signed quote and accepted assets.

03 · PROOF

Submit payment

Client submits payment proof on Base 8453 to /v1/x402/proof/submit with X-Payment header.

04 · EXECUTE

Endpoint runs

Hive verifies the on-chain payment, executes the requested workload, generates the dual-signed receipt.

05 · RECEIPT

Signed return

Client receives the signed receipt referencing the on-chain payment tx and the workload output.

Quote request and response.

# Request
POST /v1/x402/quote
Content-Type: application/json

{
  "workload": "entropy.sample",
  "params": { "bytes": 32 },
  "client_did": "did:hive:agent.acme"
}

# Response
{
  "quote_id": "qte_x402_3a91e2c0...",
  "price": { "asset": "USDC", "amount": "0.0001", "chain_id": 8453 },
  "treasury": "0x15184Bf50B3d3F52b60434f8942b7D52F2eB436E",
  "expires_at": 1778414289.591,
  "sig_ed25519_b64u": "4oqQKBNgRM8EoFKAki...",
  "did": "did:hive:hivemorph"
}
    

Payment proof submission.

# Request
POST /v1/x402/proof/submit
X-Payment: base8453:tx:0x9f8b40eed3879030cafe1234abcd5678...
Content-Type: application/json

{
  "quote_id": "qte_x402_3a91e2c0...",
  "payer_did": "did:hive:agent.acme",
  "tx_hash": "0x9f8b40eed3879030cafe1234abcd5678ef90112233445566778899aabbccddee"
}

# Response
{
  "receipt_id": "rcp_x402_a04e2c1f...",
  "workload_output": { "sample_hex": "9f8b40ee...", "bytes": 32 },
  "payment": { "tx_hash": "0x9f8b40ee...", "chain_id": 8453, "confirmed": true },
  "sig_ed25519_b64u": "4oqQKBNgRM8EoFKAki...",
  "sig_mldsa65_b64u": "Sdy4QPkwR3v8H9TK...",
  "did": "did:hive:hivemorph"
}
    

Interop.

Hive's x402 implementation is checked against the major facilitators and agent runtimes shipping x402-compatible payment hooks today.

Anthropic MCP

Model Context Protocol payment hooks. Hive endpoints register as MCP resources with priced tools.

Google A2A

Agent2Agent protocol with AP2 extension. Agent card discoverable at the canonical well-known path.

Skyfire

Agent identity and metered access compatible with Skyfire's payment broker flow.

Crossmint

USDC and stablecoin settlement on Base via Crossmint's payment infrastructure.

Coinbase Commerce

Native Base 8453 settlement aligned with Coinbase Commerce's x402 facilitator path.

Hive Platform

Reference implementation of every x402 hook. Read the platform overview.

Get your DID + first receipt See pricing