Curve fi
Curve fi swaps exchange tokens, while loans commit collateral and create debt
Curve fi offers different ways to obtain tokens: exchange an existing balance through a swap, or borrow against eligible collateral. Before signing, compare the required assets, spending permission, expected receipt, and continuing obligations. A swap needs an acceptable minimum output. A loan also needs borrowing capacity and a workable collateral position. Confirmation should establish that the intended operation succeeded, because an approved token allowance alone proves neither an exchange nor a loan.
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Exchanging a balance or committing collateral
A swap fits an outright exchange: the input leaves your balance, and the output replaces it. Borrowing commits collateral while creating a separate debt. Both require executable terms, although their costs and remaining obligations differ substantially after confirmation.
For the borrowing option, distinguish mint markets from lending markets. Mint markets create crvUSD against eligible collateral; lending markets draw on supplied assets. That funding difference affects availability. A visible market doesn’t establish that your requested loan can execute. Compare the selected collateral, borrowed token, available capacity, and proposed position before treating borrowing as an alternative to selling.
Balances and market capacity before approval
Spendable tokens and network gas are separate prerequisites. A sufficient token balance doesn’t establish that the wallet can pay transaction costs.
Match the wallet account, selected network, and token contract to the intended operation. For a swap, the relevant input is the token being sold. For a loan, the market must accept the collateral that you intend to commit. Token symbols alone don’t identify contracts, and a balance displayed for another network doesn’t satisfy the selected contract’s requirements.
Borrowing capacity also depends on the market’s rules and available funds. Llamalend v2 enforces a configurable borrowing cap alongside collateral constraints. Its health preview and maximum borrowing calculation answer different questions: the predicted health of the proposed position, and the amount borrowable given collateral, market caps, and available liquidity. Neither figure represents a permanent entitlement.
These parameters have transaction-specific or market-specific values. They should remain attached to the exact token, spender, or market being considered.
| Parameter | Value used | What it limits | Applicable scope |
|---|---|---|---|
| Token allowance | Remaining approved token quantity | Transfers authorized for the spender | One owner’s token balance and the specified spender |
| Minimum output | Lower bound submitted with the swap | Output below which execution reverts | The selected swap’s output token |
| Borrow cap | Configured market debt ceiling | Additional borrowing | The selected Llamalend v2 lending market |
| An allowance authorizes spending; swap and loan parameters separately determine whether the requested operation can execute. | |||
What does the wallet confirmation commit?
Confirming in the wallet authorizes the displayed transaction; its effects depend on successful onchain execution. An approval changes spending permission; a swap exchanges assets; loan creation commits collateral and records debt.
Permission and execution require different checks
The approval request
An ERC-20 allowance lets a specified spender transfer tokens from the owner’s balance up to the authorized amount. Compare the spender and amount with the operation you intended. A broad allowance can remain useful to that spender beyond this transaction, so its scope deserves a separate decision.
The swap or loan request
For a swap, review the input quantity, output token, minimum received, and recipient where the transaction supports a separate recipient. A loan request also needs its collateral amount, debt amount, and position preview checked together. If the transaction includes leverage or another bundled operation, its asset movements extend beyond plain borrowing. Don’t assume that every request following an approval has the same effect.
Signing approval doesn’t complete the intended swap or create the intended loan. The execution transaction has its own result.
Swap costs and continuing loan obligations
A swap quote reflects execution through liquidity pools, including the pool fees. Network gas is a separate cost. Price impact describes how the trade affects execution prices; minimum received sets the output boundary that the submitted swap must satisfy. Increasing tolerance doesn’t improve the pool’s liquidity or remove the trade’s price impact.
Borrowing adds costs that continue after confirmation. Interest increases outstanding debt while the loan remains open, and the applicable rate can change. The amount received at creation therefore isn’t necessarily the amount needed for eventual repayment. Compare that ongoing obligation with the immediate exchange represented by a swap.
Collateral exposure can change inside the liquidation range
LLAMMA gradually exchanges collateral for the borrowed token as prices move through the position’s liquidation range. Those conversions can produce losses. A price recovery can reverse their direction without restoring value lost during earlier exchanges. Full liquidation remains possible if position health deteriorates sufficiently. Before confirming a loan, the range and health preview matter alongside the borrowed amount.
Match the receipt to the intended asset change
A successful approval receipt establishes permission, while a successful swap receipt should correspond to the intended token transfers. Compare the output-token transfer’s recipient and amount with the intended receiving account and its balance change. The token contract and its decimals determine how raw transfer quantities translate into displayed amounts. A transaction hash alone doesn’t explain which operation succeeded.
For a plain loan, verify both the position record and receipt of the borrowed tokens. For a leveraged or bundled loan, verify the position record and the asset movements specified by that operation. The selected market should show the collateral commitment and outstanding debt for the correct account. An ordinary swap creates no pool-share position; providing liquidity is a different operation. Likewise, a loan remains open after the borrowed tokens arrive. Its receipt confirms creation, while the position record describes the continuing obligation.
A failed swap with an unchanged balance
An unchanged input balance after a reverted swap is consistent with the exchange having failed. Gas may still have been spent.
Read the existing transaction’s status before submitting another request. A pending transaction hasn’t established success or failure. A reverted transaction doesn’t justify widening slippage automatically: price movement beyond minimum received is one possible cause, and the fresh quote may represent different terms. Keep an already confirmed approval separate from the failed exchange when examining the records.
A replacement swap should reflect a fresh quote and an acceptable output boundary. Borrowing introduces collateral requirements, interest, and liquidation exposure, so it isn’t a repair for an unsuccessful exchange. If the task remains an outright token conversion, compare another supported swap quote with stopping before another commitment.
Questions and answers about Curve fi
Can a different swap route reuse an existing token approval?
An existing approval is reusable only when it covers the required token, spender, and amount. A different route may retain the same router, or it may require a different spending contract. Compare the requested spender with the existing allowance instead of assuming that every Curve operation shares permission.
Do borrowed tokens have to remain in the wallet until repayment?
Borrowed tokens can leave the wallet without closing the loan. The debt remains associated with the borrowing position, and committed collateral remains subject to the market’s rules. Spending or transferring the proceeds therefore doesn’t remove interest accrual or the need to obtain sufficient assets for repayment.
Is the original borrowed amount enough to close a Curve loan?
The original borrowed amount may be insufficient because interest increases outstanding debt. Full closure requires repayment of the debt then owed, rather than simply returning the initial proceeds. A partial repayment reduces the obligation but doesn’t establish that the position has closed. Check the resulting debt record.
What happens if I reject the swap after approving its token?
Rejecting the swap request doesn’t undo a separately confirmed approval. The exchange hasn’t executed, but the spender may retain its token allowance. Closing the interface also leaves that onchain permission unchanged. Changing or removing an allowance is a separate operation from declining the proposed swap.
Will a completed swap earn liquidity-provider fees?
An ordinary completed swap doesn’t create a liquidity-provider position. Pool shares arise from supplying liquidity through a deposit operation. If the intended outcome was simply to receive another token, a request involving a liquidity deposit represents a different commitment and needs its own review before signing.