# Core protocol functions

### Create a contingent pool

```
function createContingentPool(
    PoolParams calldata _poolParams
) 
    external;
```

where `PoolParams` contains the following list of parameters in the corresponding order:

<table><thead><tr><th width="204.37209302325581">Parameter</th><th width="150" align="center">Type</th><th width="150">Category</th><th>Description</th></tr></thead><tbody><tr><td><code>referenceAsset</code></td><td align="center">string</td><td>Event</td><td>The metric or event whose outcome will determine the payout for long and short position tokens.</td></tr><tr><td><code>expiryTime</code></td><td align="center">uint96</td><td>Event</td><td>Expiration time of position tokens expressed as a unix timestamp in seconds. The value of the reference asset observed at that point in time determines the payoffs for long and short position tokens.</td></tr><tr><td><code>floor</code></td><td align="center">uint256</td><td>Payoff</td><td>Value of the reference asset at or below which the long token pays out 0 and the short token 1 (max payout). Input expects an integer with 18 decimals.</td></tr><tr><td><code>inflection</code></td><td align="center">uint256</td><td>Payoff</td><td>Value of the reference asset at which the long token pays out <code>gradient</code> and the short token <code>1-gradient</code>. Input expects an integer with 18 decimals.</td></tr><tr><td><code>cap</code></td><td align="center">uint256</td><td>Payoff</td><td>Value of the reference asset at or above which the long token pays out 1 (max payout) and the short token 0. Input expects an integer with 18 decimals.</td></tr><tr><td><code>gradient</code></td><td align="center">uint256</td><td>Payoff</td><td>Long token payout at inflection (value between 0 and 1). Input expects an integer with 18 decimals.</td></tr><tr><td><code>collateralAmount</code></td><td align="center">uint256</td><td>Payoff</td><td>Collateral amount to be deposited into the pool to back the position tokens. Input expects an integer with collateral token decimals.</td></tr><tr><td><code>collateralToken</code></td><td align="center">address</td><td>Settlement asset</td><td>Address of the ERC20 collateral token.</td></tr><tr><td><code>dataProvider</code></td><td align="center">address</td><td>Oracle</td><td>Ethereum account (EOA or smart contract) that will report the final reference asset value.</td></tr><tr><td><code>capacity</code></td><td align="center">uint256</td><td>Pool size</td><td>Maximum collateral amount that a contingent pool can accept. Choose a large number (e.g., <code>2**256 - 1</code>) for unlimited size. Input expects an integer with collateral token decimals.</td></tr></tbody></table>

### Adding liquidity

Add liquidity to an existing pool using the following function:

```
function addLiquidity(
    uint256 _poolId,                // Id of the pool that a user wants to add collateral to
    uint256 _collateralAmountIncr   // Incremental collateral amount to be added to the pool expressed as an integer with collateral token decimals
) 
    external;
```

### Removing liquidity

Remove liquidity from an existing pool using the following function:

```
function removeLiquidity(
    uint256 _poolId,  // Id of the pool that a user wants to remove collateral from 
    uint256 _amount   // Number of position tokens to return (expressed as an integer with position token decimals)
) 
    external;
```