For pool 3:
Fuse is an exciting new product by Rari that allows you to borrow, long or short any asset against any other asset. To iterate quickly and obtain real market data, pools were created and parameters were set intuitively. Now that we are more mature we are looking to establish a more standardised and data-driven approach to risk.
Resource: A standard risk model for Fuse
Applying these principles to Fuse Pool 3 yields a number of desirable and potentially necessary changes to safeguard user interests.
Changes are guided by the proposed risk model (linked above).
Change 1: Liq incentive to 30% As described in our model, protocol only needs to absorb shock, whereas liquidators need to absorb shock, slippage and gas. Therefore 8% incentive for liquidators is too low and leftover allowance for protocol (100% - 8% - cf) is unnecessarily high.
This is a high risk pool comprising of numerous volatile and illiquid assets - where all assets can be borrowed against each other. Therefore shock allowance will be decided by the most potentially volatile asset in the pool. We will allow 20% for shock.
Since some assets are illiquid, 10% has been allowed for slippage (or gas).
Change 2: Change CFs Keeping in mind a liq incentive of 30% and a slippage allowance of 10%, we can set CFs based on shock tolerances of individual assets. These get set in the 50-70% range due to 20% max shock tolerance and 30% liq incentive. Less volatile assets get higher CFs.
Change 3: Set 100% util rates to 700% Since all assets can be borrowed against each other, it does not make sense to set different wind-down periods for different assets. A wind-down period of 2 month may be ideal. This corresponds to a 100% util rate of around 700%
Change 4: Change 80% util rates 80% util rates are to be set based on the maximum borrowers will be willing to pay for the likely use cases.
Use case of USDC, DAI is borrowing and longing other assets. There may be high demand for this so 80% has been set.
Use case for most other assets is shorting. Higher interest rates are charged on more volatile assets due to higher potential profits and risks involved.
Suggested rates are experimental, and may be lowered in the future if sufficient borrow demand is not found.
Change 5: Recommend collateral caps at 10% slippage for those assets Since we have allowed a 10% slippage tolerance, we will also recommend collateral caps at 10% slippage.
Suppose LINK-ETH has liquidity primarily on Uniswap and this liquidity is 1,300,000 LINK against 22,300 ETH. Selling 65,000 LINK will cause 10% slippage, hence this Fuse pool will have a recommended supply cap of 65,000 LINK.
If this Fuse pool has more than 65,000 LINK deposited, the risk of this pool increases and appropriate action such as decreasing collateral factor or implementing a supply cap may be needed.
DAO Fuse pools must ensure relative safety of both their lenders and borrowerers under extreme market conditions, while simultaneously being able to offer high risk products such as leverage and shorting on illiquid assets. We believes these parameters meaningfully capture this tradeoff.
At the same we do not wish to disturb the user experience of those who are already using these pools. Although liquidation incentive has increased, collateral factors have also been increased for many assets - leading to an overall better user experience.
An attempt has been made to ensure interest rates are competitive and maximise both lenders' yield and protocol revenue, without trampling over borrower interests. High rates at 100% utilisation may prove necessary from a risk perspective, especially in these early days.