> For the complete documentation index, see [llms.txt](https://docs.usenest.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.usenest.xyz/trading/3.2-routing-and-errors.md).

# 3.2 - Routing & Errors

The **nest router** automatically searches across all available pools to find the most efficient execution path for your swap. A trade may route through multiple pools (multi-hop) if that delivers a better net output than a single direct swap.

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### How routing works

* You request a swap from Token A → Token B
* The router scans all available paths: direct A→B, A→USDH→B, A→WHYPE→B, and more
* It selects the path that maximises your output after all fees
* The route is shown in the swap interface before you confirm

{% hint style="info" %}
HYPE → TOKEN may route as **HYPE → USDH → TOKEN** if that path has deeper liquidity and lower total price impact — even though it uses two pools and two fee hops.
{% endhint %}

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### When routing looks unexpected

* The direct pool may have low liquidity → multi-hop is better
* New or low-liquidity tokens may route imperfectly until liquidity deepens
* If the route looks very inefficient: reduce size and retry, or wait for more liquidity

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### Common Swap Errors

<table><thead><tr><th width="193.0234375">Error</th><th>Cause</th><th>Fix</th></tr></thead><tbody><tr><td><strong>Insufficient output / Slippage exceeded</strong></td><td>Price moved outside your slippage tolerance</td><td>Increase slippage slightly or reduce trade size</td></tr><tr><td><strong>Insufficient gas</strong></td><td>Not enough HYPE in wallet for gas</td><td>Add HYPE to your wallet — HYPE is the gas token on HyperEVM</td></tr><tr><td><strong>Approval required</strong></td><td>Token hasn't been approved for the router</td><td>Approve the token (first time only per token)</td></tr><tr><td><strong>Transaction reverted</strong></td><td>Slippage, gas, or pool state changed</td><td>Refresh and retry; check slippage and gas</td></tr><tr><td><strong>Route not found</strong></td><td>No liquidity path exists for this pair</td><td>Try routing manually through USDH or WHYPE, or wait for liquidity</td></tr></tbody></table>

{% hint style="info" %}
**Most common issue:** not enough HYPE for gas. Always keep some HYPE in your wallet on HyperEVM — even a small amount covers most transactions.
{% endhint %}