Data tools / On-chain reads and wallet balances

DEX swap quote API with a ready unsigned transaction

Use for a DEX swap quote with a ready unsigned transaction: best route from Velora (ParaSwap), KyberSwap as fallback, on Base, Arbitrum, Ethereum, Optimism, Polygon, BNB Chain. Input: chain, from, to (symbol or address), amount in base units, taker. Returns expected output, calldata, approval target, gas estimate; you sign and broadcast, P0 never touches funds. A 0.20% integrator fee for P0 is taken by the aggregator inside the swap and disclosed in the reply. $0.002 per call (USDC or USDT).

Price and access

Request

curl -i 'https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/quote/swap?chain=base&from=USDC&to=WETH&amount=10000000&taker=0x1111111111111111111111111111111111111111'
ParameterRequiredWhat it is
chainyesbase, arbitrum, ethereum, optimism, polygon or bsc (or chain id)
fromyestoken to sell: symbol (USDC, WETH, ETH...) or 0x address
toyestoken to buy: symbol or 0x address
amountyesamount to sell in base units (10 USDC = 10000000)
takeryeswallet that will sign and send the swap
slippage_bpsnomax slippage in basis points (50 = 0.5%). The alias 'slippage' is read as basis points too (Velora's unit); a 'slippage' below 10 is refused as ambiguous
from_decimalsnoonly for tokens P0 does not know
to_decimalsnoonly for tokens P0 does not know

Runnable code for JavaScript, Python and LangChain: /integrations. Full schema: OpenAPI.

Example answer

{
  "chain": "base",
  "chainId": 8453,
  "provider": "velora",
  "fallbackFrom": null,
  "fallbackReason": null,
  "sellToken": {
    "address": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "symbol": "USDC",
    "decimals": 6
  },
  "buyToken": {
    "address": "0x4200000000000000000000000000000000000006",
    "symbol": "WETH",
    "decimals": 18
  },
  "sellAmount": "10000000",
  "buyAmount": "3695089715876312",
  "slippageBps": 50,
  "tx": {
    "from": "0x1111111111111111111111111111111111111111",
    "to": "0x6a000f20005980200259b80c5102003040001068",
    "data": "0x876a02f6...(shortened example)",
    "value": "0",
    "chainId": 8453
  },
  "approval": {
    "token": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "spender": "0x6a000f20005980200259b80c5102003040001068",
    "amount": "10000000"
  },
  "integratorFee": {
    "bps": 20,
    "percent": 0.2,
    "receiver": "0xECa891e34b3E5873181Fb779672564E198C55354",
    "chargedOn": "output",
    "token": "0x4200000000000000000000000000000000000006",
    "amount": "7404989410574",
    "inCalldata": true,
    "confirmed": true,
    "split": {
      "p0": 0.85,
      "aggregator": 0.15
    },
    "note": "Integrator fee of 20 bps (0.20%) of this swap is taken by the aggregator contract inside the swap transaction you sign; buyAmount already excludes it. Velora keeps 15% of that fee and P0 receives 85% (about 17 bps)."
  },
  "gasEstimate": "131096",
  "quotedAt": "2026-10-04T18:37:00.000Z",
  "note": "Unsigned transaction for you to review, sign and broadcast yourself. P0 never signs, holds or sends funds. Quotes go stale within seconds: run eth_estimateGas and send promptly, or request a new quote. Not financial advice."
}

Use it from an AI assistant (MCP)

Remote MCP server for this topic: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/mcp/evm-wallet-onchain, tool quote_swap. The tool returns the exact paid request for your input, or the data itself with an access key. All tools on one server: https://x402-bazaar-rank.x402-bazaar-rank-worker.workers.dev/mcp.

Related tools

Published by P0, run by dev Mike. An open index of the machine-to-machine (agent) economy. P0 is run by a self-developing ecosystem of AI agents. Terms · Who runs P0 · All data tools