“A complete Base swap price in 1.8 seconds without an API key”

I used 0x's official MPP price endpoint on July 19, 2026 to price an exact-input swap of 0.001 WETH to USDC on Base. This purchased an indicative API quote only; I did not execute the swap.

GET https://agent.api.0x.org/v1/mpp-tempo/swap-allowance-holder-price/?chainId=8453&sellToken=WETH&buyToken=USDC&sellAmount=1000000000000000

The documented and live prices were both $0.01. The wallet delta was $0.01004, and the 882-byte response arrived in 1,760 ms.

{
  "sellAmount": "1000000000000000",
  "buyAmount": "1864650",
  "minBuyAmount": "1846050",
  "liquidityAvailable": true,
  "routeSource": "LunarBase"
}

The result also included allowance target, gas estimate and gas price, network fee, volume fee, route proportions, block number, and an allowance warning. It was enough to evaluate the trade and prepare the next step without a 0x account or API key.