Adapter routing

Adapter	Priority	Target	Use case
X402Adapter	70	https://… URLs	Instant atomic HTTP payments — direct USDC settlement
StandardAdapter	60	0x… addresses	Full ACTP lifecycle — create, accept, link, transition, settle
BasicAdapter	50	0x… addresses	High-level pay() — create + escrow to COMMITTED in one call

• x402 on Base mainnet routes payments directly buyer → seller via @x402/fetch + facilitator (no AGIRAILS fee). Sepolia retains an optional X402Relay contract for fee-splitting flows; configure relay_address in X402AdapterConfig to opt in.
• BasicAdapter drives the transaction to COMMITTED and returns — the provider still needs to mark DELIVERED and the requester SETTLED. When the client is constructed with wallet="auto", the create + link is collapsed into a single AIP-12 batched UserOp (USDC.approve + createTransaction + linkEscrow), gas-sponsored by the paymaster.

See also

• x402 v2 detail
• Gasless payment recipe
• SDK reference — adapters