# Provide Fee AMM Liquidity

## Overview

The Fee AMM converts a user's fee token into the token a validator wants to be paid in. Liquidity
providers supply both sides of a pool and earn from the conversions that flow through it. You can add
liquidity, read pool reserves and your LP balance, remove liquidity, and rebalance a pool.

[See the Fee AMM specification](https://docs.tempo.xyz/protocol/fees/spec-fee-amm)

## Recipes

These recipes assume you have [set up a Tempo client](/tempo).

### Add Liquidity

Add liquidity to a pool with [`amm.mintSync`](/tempo/actions/amm.mint). LP shares are minted to the
`to` address.

:::code-group
```ts twoslash [example.ts]
import { parseUnits } from 'viem'
import { client } from './viem.config'

const { receipt } = await client.amm.mintSync({
  userTokenAddress: '0x20c0000000000000000000000000000000000001',
  validatorTokenAddress: '0x20c0000000000000000000000000000000000002',
  validatorTokenAmount: parseUnits('100', 6),
  to: client.account.address,
})
```

```ts twoslash [viem.config.ts] filename="viem.config.ts"
// [!include ~/snippets/tempo/viem.config.ts:setup]
```
:::

### Read Pool State

Read pool reserves with [`amm.getPool`](/tempo/actions/amm.getPool) and your LP balance with
[`amm.getLiquidityBalance`](/tempo/actions/amm.getLiquidityBalance).

:::code-group
```ts twoslash [example.ts]
import { client } from './viem.config'

const userToken = '0x20c0000000000000000000000000000000000001'
const validatorToken = '0x20c0000000000000000000000000000000000002'

const pool = await client.amm.getPool({ userToken, validatorToken })

const balance = await client.amm.getLiquidityBalance({
  userToken,
  validatorToken,
  address: client.account.address,
})
```

```ts twoslash [viem.config.ts] filename="viem.config.ts"
// [!include ~/snippets/tempo/viem.config.ts:setup]
```
:::

### Remove Liquidity

Burn LP shares to withdraw your underlying tokens with [`amm.burnSync`](/tempo/actions/amm.burn).

:::code-group
```ts twoslash [example.ts]
import { client } from './viem.config'

const { receipt } = await client.amm.burnSync({
  userToken: '0x20c0000000000000000000000000000000000001',
  validatorToken: '0x20c0000000000000000000000000000000000002',
  liquidity: 50n,
  to: client.account.address,
})
```

```ts twoslash [viem.config.ts] filename="viem.config.ts"
// [!include ~/snippets/tempo/viem.config.ts:setup]
```
:::

### Rebalance a Pool

Swap against a pool to rebalance its reserves with
[`amm.rebalanceSwapSync`](/tempo/actions/amm.rebalanceSwap).

:::code-group
```ts twoslash [example.ts]
import { client } from './viem.config'

const { receipt } = await client.amm.rebalanceSwapSync({
  userToken: '0x20c0000000000000000000000000000000000001',
  validatorToken: '0x20c0000000000000000000000000000000000002',
  amountOut: 100n,
  to: client.account.address,
})
```

```ts twoslash [viem.config.ts] filename="viem.config.ts"
// [!include ~/snippets/tempo/viem.config.ts:setup]
```
:::

## Best Practices

### Mint to a Canonical Account

LP shares are bound to the address you mint them to, and only that address can burn them. Mint to a
canonical account you control. Never mint LP shares to a [virtual address](/tempo/guides/virtual-addresses),
because such shares become permanently unburnable.

### Read Reserves Before Rebalancing

Check pool reserves with `amm.getPool` before a rebalance swap so you know the current ratio and
don't push the pool further from balance than you intend.

### Keep Popular Fee Tokens Liquid

Fees only settle smoothly when the relevant pool has liquidity. If you issue or rely on a particular
fee token, keeping its Fee AMM pool funded keeps fee conversions cheap and reliable for your users.

## See More

<Cards>
  <Card icon="lucide:hand-coins" title="Pay Fees in a Stablecoin" description="How the Fee AMM converts fee tokens behind the scenes." to="/tempo/guides/pay-fees" />

  <Card icon="lucide:arrow-left-right" title="Swap Stablecoins" description="Trade stablecoins on the enshrined Stablecoin DEX." to="/tempo/guides/stablecoin-exchange/swap" />

  <Card icon="lucide:square-function" title="amm.mint" description="Add liquidity to a Fee AMM pool." to="/tempo/actions/amm.mint" />

  <Card icon="lucide:book-open" title="Tempo Docs: Fee AMM" description="The Fee AMM design and fee conversion model." to="https://docs.tempo.xyz/protocol/fees/spec-fee-amm" />
</Cards>