Operate a Stablecoin
This guide covers how to manage a Monolith stablecoin instance as an operator or manager. These roles have limited powers to tune parameters before the immutability deadline.
Roles Overview
Operator
The operator has the highest instance-level authority:
- Can adjust all tunable parameters
- Can set local reserve fees
- Can transfer operator role
- Can appoint and remove managers
- Can trigger immediate immutability
- Can pull local reserves
Manager
The manager has delegated authority from the operator:
- Can adjust interest rate parameters
- Cannot modify fees or transfer roles
- Useful for day-to-day parameter management
Both roles become powerless after the immutability deadline.
Parameters You Can Adjust
All parameter changes must occur before the immutability deadline.
Interest Rate Parameters
Half-Life
Controls how quickly the borrow rate changes:
function setHalfLife(uint64 halfLife) external
- Range: 12 hours to 30 days
- Effect: Shorter = faster rate adjustments; longer = smoother changes
- Access: Operator or Manager
Target Free Debt Ratio
Defines the target band for the free debt share:
function setTargetFreeDebtRatio(uint16 startBps, uint16 endBps) external
- startBps: Lower bound (≥500 bps)
- endBps: Upper bound (≤9500 bps)
- Effect: Narrower band = more reactive rates; wider = more stable
- Access: Operator or Manager
Fee Parameters
Redemption Fee
Fee charged when users redeem Coin for collateral:
function setRedeemFeeBps(uint16 _redeemFeeBps) external
- Range: 0 to 300 bps (0-3%)
- Effect: Higher = more protection for free debt borrowers; lower = better redemption UX
- Access: Operator or Manager
Local Reserve Fee
Portion of interest directed to operator reserves:
function setLocalReserveFeeBps(uint _feeBps) external
- Range: 0 to 1000 bps (0-10%)
- Effect: Revenue for instance operator
- Access: Operator only
Role Management
Transfer Operator Role
Operator transfer is a two-step process for safety:
// Step 1: Current operator sets pending operator
function setPendingOperator(address _pendingOperator) external
// Step 2: Pending operator accepts
function acceptOperator() external
Set Manager
function setManager(address _manager) external
- Can be called by operator or current manager
- Set to
address(0) to remove manager role
Immutability
Understanding the Deadline
Each instance has an immutability deadline set at deployment:
immutabilityDeadline = deployTimestamp + timeUntilImmutability
- No parameter changes allowed
- Operator/manager roles become inactive
- Instance runs autonomously forever
Triggering Early Immutability
Operators can make the instance immutable immediately:
function enableImmutabilityNow() external
This is irreversible. Once triggered, no further parameter changes are possible.
Revenue Collection
Local Reserves
Pull accumulated local reserves (from interest fees and PSM profits):
function pullLocalReserves() external
- Mints accrued reserves as Coin to the operator
- Automatically accrues any PSM vault profit first
- Access: Operator only
Global Reserves
Global protocol reserves are pulled by the Factory operator, not the instance operator.
Operational Best Practices
Parameter Tuning
Interest Rate Management
- Monitor free debt ratio: Track
getFreeDebtRatio() regularly
- Adjust target band: Widen if rate volatility is too high
- Tune half-life: Increase if rates change too rapidly
Fee Optimization
- Redemption fee: Balance borrower protection vs redemption attractiveness
- Local reserve fee: Consider sustainable revenue vs competitive rates
Monitoring Checklist
| Metric | Why It Matters |
|---|
| Free debt ratio | Indicates system balance and redemption liquidity |
| Borrow rate | Affects borrower costs and staker yields |
| Total paid debt | Base for interest generation |
| Total free debt | Available redemption capacity |
| Oracle health | Stale prices trigger reduce-only mode |
| Accrued reserves | Revenue available to claim |
Emergency Procedures
Oracle Issues
- Monitor for staleness (>25 hours triggers reduce-only)
- No operator action available - system handles automatically
Rate Volatility
- Increase half-life for slower adjustments
- Widen target band to reduce sensitivity
Low Free Debt
- Consider lowering redemption fee to encourage free debt
- Rates will naturally rise to incentivize free debt
Common Operations
Adjust Interest Model
// Make rate changes slower
lender.setHalfLife(7 days);
// Narrow the target band for tighter control
lender.setTargetFreeDebtRatio(2500, 3500);
Update Fees
// Reduce redemption fee to encourage redemptions
lender.setRedeemFeeBps(100); // 1%
// Increase operator revenue share
lender.setLocalReserveFeeBps(500); // 5%
Collect Revenue
// Pull accumulated reserves
lender.pullLocalReserves();
Transfer Control
// Transfer operator role
lender.setPendingOperator(newOperatorAddress);
// New operator must call: lender.acceptOperator()
// Delegate to manager
lender.setManager(managerAddress);
Quick Reference
| Function | Access | Deadline Required |
|---|
setHalfLife | Operator/Manager | Yes |
setTargetFreeDebtRatio | Operator/Manager | Yes |
setRedeemFeeBps | Operator/Manager | Yes |
setLocalReserveFeeBps | Operator | No |
setPendingOperator | Operator | No |
acceptOperator | Pending Operator | No |
setManager | Operator/Manager | No |
enableImmutabilityNow | Operator | Yes |
pullLocalReserves | Operator | No |
