DEX Swap Quotes API
Best swap quotes across DEXes (Uniswap, SushiSwap, Aerodrome). Base & Ethereum. x402.
Open source Repository Open in the app JSON README (API)
About
Best swap quotes across DEXes (Uniswap, SushiSwap, Aerodrome). Base & Ethereum. x402.
Details
- Kind
- MCP servers
- Topic
- Finance & crypto
- Publisher
- br0ski777
- Origin
- official
- Category
- ferramentas
- Transport
- sse
- Version
- 1.1.0
- Last push
- 2026-09-02T19:55:39Z
- Repository state
- ativo
- Language
- TypeScript
- License
- MIT
- Added
- 2026-08-29 03:01:43
- Updated
- 2026-08-29 03:01:43
- Origin id
io.github.Br0ski777/dex-quotes
README
# DEX Swap Quotes API
[](https://dex-quotes.api.klymax402.com/mcp)
[](https://x402.org)
[](LICENSE)
Best swap quotes across Uniswap, SushiSwap, Aerodrome -- price impact, route, slippage. Pre-trade essential. Pay-per-call via [x402](https://x402.org) (USDC on Base L2) -- no API key, no signup, no rate-limit wall.
Part of the [klymax402](https://klymax402.com) marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.
## Quickstart -- MCP
Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):
```json
{
"mcpServers": {
"dex-quotes": {
"url": "https://dex-quotes.api.klymax402.com/mcp"
}
}
}
```
## Quickstart -- HTTP (x402)
```bash
curl "https://dex-quotes.api.klymax402.com/api/quote?tokenIn=...&tokenOut=...&amount=..."
# -> 402 Payment Required, with an x402 payment challenge in the response body
```
Any x402-aware client ([`@x402/fetch`](https://www.npmjs.com/package/@x402/fetch), [`x402-agent-tools`](https://www.npmjs.com/package/x402-agent-tools), ATXP) handles the 402 -> sign -> retry cycle automatically.
## Tools
| Tool | Method | Path | Price | Description |
|---|---|---|---|---|
| `dex_get_swap_quote` | GET | `/api/quote` | $0.012 | Get the best swap quote across multiple DEXes |
| `dex_get_swap_quote` | POST | `/api/quote` | $0.012 | Get the best swap quote across multiple DEXes (POST variant) |
### `dex_get_swap_quote`
Use this when you need a swap quote before trading tokens on-chain. Returns the best price across multiple DEXes in JSON.
**Parameters**
| Name | Type | Required | Description |
|---|---|---|---|
| `tokenIn` | string | yes | Contract address of input token (e.g. 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 for USDC on Base) |
| `tokenOut` | string | yes | Contract address of output token (e.g. 0x4200000000000000000000000000000000000006 for WETH on Base) |
| `amount` | string | yes | Amount of input token in raw units (wei/smallest unit, e.g. 1000000 for 1 USDC) |
| `chain` | string | no | Blockchain network: base or ethereum (default: base) |
**Returns**
- `bestDex` -- which DEX offers the best rate (Uniswap, SushiSwap, Aerodrome)
- `amountOut` -- expected output token amount
- `priceImpact` -- percentage price impact of the trade
- `minimumReceived` -- minimum output after slippage tolerance
- `route` -- swap path (e.g. USDC -> WETH -> TOKEN)
- `gasEstimateUsd` -- estimated gas cost in USD
Example response:
```json
{"bestDex":"Uniswap V3","amountOut":"0.3215","priceImpact":"0.12%","minimumReceived":"0.3183","route":["USDC","WETH"],"gasEstimateUsd":0.04}
```
**When to use**: executing any token swap to find the best rate and estimate slippage. Essential for trade sizing and DEX comparison.
**Not for**: gas estimation only (use `gas_get_current_price`), yield opportunities (use `defi_find_best_yields`), wallet balance (use `wallet_get_portfolio`).
### `dex_get_swap_quote`
Use this when you need a swap quote before trading tokens on-chain. Returns the best price across multiple DEXes in JSON. POST variant of dex_get_swap_quote -- same params passed as JSON body instead of query string.
**Parameters**
| Name | Type | Required | Description |
|---|---|---|---|
| `tokenIn` | string | yes | Contract address of input token (e.g. 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 for USDC on Base) |
| `tokenOut` | string | yes | Contract address of output token (e.g. 0x4200000000000000000000000000000000000006 for WETH on Base) |
| `amount` | string | yes | Amount of input token in raw units (wei/smallest unit, e.g. 1000000 for 1 USDC) |
| `chain` | string | no | Blockchain network: base or ethereum (default: base) |
**Returns**
- `bestDex` -- which DEX offers the best rate (Uniswap, SushiSwap, Aerodrome)
- `amountOut` -- expected output token amount
- `priceImpact` -- percentage price impact of the trade
- `minimumReceived` -- minimum output after slippage tolerance
- `route` -- swap path (e.g. USDC -> WETH -> TOKEN)
- `gasEstimateUsd` -- estimated gas cost in USD
Example response:
```json
{"bestDex":"Uniswap V3","amountOut":"0.3215","priceImpact":"0.12%","minimumReceived":"0.3183","route":["USDC","WETH"],"gasEstimateUsd":0.04}
```
**When to use**: executing any token swap to find the best rate and estimate slippage. Essential for trade sizing and DEX comparison.
**Not for**: gas estimation only (use `gas_get_current_price`), yield opportunities (use `defi_find_best_yields`), wallet balance (use `wallet_get_portfolio`).
## Example agent prompts
- "A swap quote before trading tokens on-chain"
- "A swap quote before trading tokens on-chain"
## Payment
- Protocol: [x402](https://x402.org) -- HTTP-native pay-per-call, no signup, no API key
- Network: Base L2 (`eip155:8453`)
- Asset: USDC
- Facilitator: Coinbase CDP (primary), PayAI (fallback)
- Also reachable via [ATXP](https://atxp.ai) (OAuth-wrapped x402, RFC 9728 protected-resource metadata)
## Part of klymax402
100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.
- Catalog: https://klymax402.com/llms.txt
- Full API reference: https://klymax402.com/llms-full.txt
- Live stats: https://klymax402.com/stats
## License
MIT