> ## Documentation Index
> Fetch the complete documentation index at: https://docs.base.org/llms.txt
> Use this file to discover all available pages before exploring further.

# KyberSwap

> Best-rate DEX aggregation through KyberSwap routes and Base MCP send_calls across supported EVM chains.

KyberSwap is a DEX aggregator that routes trades across 50+ liquidity sources. The plugin fetches a route quote, builds unsigned calldata with the KyberSwap Aggregator API, and submits the swap through Base MCP `send_calls`.

**Chains:** Base, Ethereum, Arbitrum, Optimism, Polygon, BSC, and Avalanche.

**Operations:** token resolution, best-route quotes, swap calldata building, ERC-20 approvals, and native-token swaps.

<Tip>
  **Multi-chain swaps.** Use chain name strings such as `base`, `arbitrum`, or `polygon`, not numeric chain IDs. Quotes can move, so the assistant confirms output, gas, and slippage first.
</Tip>

## Try it

```text Base swap theme={null}
Swap 100 USDC to ETH on Base
```

```text Arbitrum swap theme={null}
Swap 0.1 ETH to USDC on Arbitrum
```

```text Read-only quote theme={null}
What's the best rate to swap 500 MATIC to USDC on Polygon?
```

## Pattern

The assistant calls `GET /api/v1/routes`, shows the quoted output and gas, then calls `POST /api/v1/route/build` with the returned `routeSummary`. Native-token input maps to one router call. ERC-20 input batches an ERC-20 `approve` call before the router call.

`transactionValue` is returned as decimal wei and must be hex-encoded for Base MCP `send_calls`.

## Reference

<Card title="Full plugin spec on GitHub" icon="github" href="https://github.com/base/skills/blob/master/skills/base-mcp/plugins/kyberswap.md">
  Route API, build API, chain slugs, approval encoding, and send\_calls mapping.
</Card>