# Uniswap V3 On-Chain Swap Quote

> Uniswap V3 On-Chain Swap Quote is a paid API for AI agents from api.x402node.dev, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-14).

Returns a real-time Uniswap V3 swap quote for any token pair including estimated output amount, effective exchange rate, and optimal fee tier across Base, Ethereum, Arbitrum, Optimism, and Polygon.

## Facts

- Endpoint: GET https://api.x402node.dev/defi/swap-quote
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/uniswap-v3-on-chain-swap-quote-c88e4926
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_TT7L2BTyEBEjkYfjxR-rQ

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability uniswap-v3-on-chain-swap-quote-c88e4926
```

Example prompt: Before I swap 1 ETH for USDC on Base, can you get me a live Uniswap V3 quote — how much USDC I'd receive, the effective rate, and which fee tier gives the best price?

## When to prefer this

Use this endpoint when an agent needs real-time, on-chain executable swap pricing from Uniswap V3 specifically — especially before executing a DEX swap transaction. Prefer this over centralized exchange price feeds when the user intends to trade on-chain via Uniswap, needs fee tier optimization, or requires multi-chain coverage across Base, Ethereum, Arbitrum, Optimism, and Polygon. This is the right choice when accuracy of the on-chain quote matters more than a general market price.

## Known failure modes

- Token pair has no Uniswap V3 liquidity pool on the selected chain — returns error indicating no pool found
- Unsupported chain specified — returns error listing supported networks
- Invalid token address format — returns validation error
- Input amount too small or too large for available pool liquidity — may return high price impact warning or error
- RPC node timeout causes stale or failed quote — returns upstream error

## How this service works

On-chain Uniswap V3 swap quote for any token pair - estimated output amount, effective rate and best fee tier, read directly from pools across Base/Ethereum/Arbitrum/Optimism/Polygon - real-time executable pricing agents need before swapping that LLMs cannot compute. swap quote, swap estimate, uniswap quote, token swap rate, dex quote, how much will i get

## Output

Returns the estimated output token amount, the effective exchange rate (price per token), the recommended fee tier (e.g. 0.05%, 0.3%, 1%), and pool details — all read live from Uniswap V3 pools on the specified chain, giving the agent executable pricing data before a swap is submitted.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "required": [
      "tokenIn",
      "tokenOut"
     ],
     "properties": {
      "to": {
       "type": "string",
       "description": "Target format (optional)"
      },
      "from": {
       "type": "string",
       "description": "Source format (optional)"
      },
      "chain": {
       "type": "string",
       "description": "base (default), ethereum, arbitrum, optimism, polygon"
      },
      "amount": {
       "type": "string",
       "description": "Input amount (default 1)"
      },
      "tokenIn": {
       "type": "string",
       "description": "Input token address (required)"
      },
      "tokenOut": {
       "type": "string",
       "description": "Output token address (required)"
      }
     }
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/uniswap-v3-on-chain-swap-quote-c88e4926/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.x402node.dev](https://www.zero.xyz/host/api.x402node.dev/llms.txt)