> ## Documentation Index > Fetch the complete documentation index at: https://docs.trusset.org/llms.txt > Use this file to discover all available pages before exploring further. # Set Rate Mode > Switch the market between the raw curve, a clamped curve and a fixed rate Builds the `setRateMode` transaction that changes how the market prices borrowing. It targets the market's interest model, not the market, and only the model owner can sign it. That is the `issuer` the lender of record named at adoption, unless ownership has moved since. [Get Rate Mode](/endpoints/lending/get-rate-mode) shows the current mode and `modelOwner`. The model brings the market's interest accrual up to date under the old mode before switching, so the elapsed time is charged at the rate that actually ran. A clamp reaches every open variable-rate loan from the next accrual, not only new loans. Only a `FIXED` stamp is limited to new loans. Under `FIXED`, loans opened before the switch keep accruing on the raw, unclamped curve. ## Path Parameters Market ID. ## Body Parameters `CURVE`, `CLAMPED` or `FIXED`. `CURVE` is the utilization curve and takes no bounds. `CLAMPED` holds that curve between a floor and a cap. `FIXED` stamps one rate onto each new loan, and that rate does not move for the life of the loan. Lower bound for `CLAMPED`. Integer, 0 to 50000. Upper bound for `CLAMPED`, and required by it. Integer, 1 to 50000, and at least `rateFloorBps`. The stamped rate for `FIXED`, and required by it. Integer, 1 to 50000. It cannot exceed the market's `maxFixedRateBps` when a ceiling is recorded. Hash of the transaction you broadcast for this operation. Send it to confirm the transaction and record the result. Omit it to receive the calldata. When `txHash` is present, every other field is ignored. The three modes do not mix. A bound that belongs to another mode is refused rather than dropped, and so is any bound sent with `CURVE`. ## Switch to a Fixed Rate `FIXED` is refused with `FIXED_RATE_REQUIRES_TERMS` until the market runs a maximum loan duration, set with [Set Term Config](/endpoints/lending/set-term-config). A terminal due date alone does not satisfy it. A fixed rate removes the curve's pull toward repayment, and the term clock replaces it. A stamped loan keeps its rate through every later change, including a switch back to `CURVE`. It cannot draw more: [Borrow More](/endpoints/lending/borrow-more) refuses it with `FIXED_RATE_LOAN`, so a further draw is a new loan at the terms then in force. While the model stamps a fixed rate, loan terms cannot be switched off. A clamp never blocks a borrow. Once the raw curve crosses `rateCapBps` the rate stays at the cap, and liquidity alone limits the borrow. ## Confirm the Change Send the mined hash back to this path as `{ "txHash": "0x..." }`. The API checks that the transaction called `setRateMode` on the market's interest model. It then reads the offering back from the chain and updates the market record. ## Response Fields The calldata response carries the transaction twice. `transaction` holds `to` and `data`. The same `to` and `data` also sit directly on `data`, and that is where the `chainId` and `value` binding lands, so sign from those four fields. `SIGN_TRANSACTION`. Returned when `txHash` is omitted. `{ to, data }` for the `setRateMode` call on the interest model. Returned when `txHash` is omitted. The interest model address. Returned when `txHash` is omitted. The encoded `setRateMode` call. Returned when `txHash` is omitted. Always `"0"`. Returned when `txHash` is omitted. The chain your instance resolves to. Returned when `txHash` is omitted. `setRateMode`, or the verified function when confirming. `INTEREST_MODEL_OWNER`. Returned when `txHash` is omitted. Plain-language summary of the change. Returned when `txHash` is omitted. The model owner, the one wallet that can sign. `null` when the owner could not be read. Returned when `txHash` is omitted. `true` when the owner is a verified wallet of your instance, `false` when it is not, `null` when the owner could not be read. The build is never refused on it. Returned when `txHash` is omitted. The owner, when your instance holds it. Otherwise `null`. Returned when `txHash` is omitted. Says the owner could not be read, or what to do when your instance cannot sign: hand the calldata to the owner, because any other wallet reverts `OwnableUnauthorizedAccount`. `null` when your instance holds the owner wallet. Returned when `txHash` is omitted. `{ endpoint, field }`: the call that confirms this transaction, and the body field that carries the hash. Returned when `txHash` is omitted. Transaction hash. Returned when confirming. The wallet that sent the transaction. Returned when confirming. Block the transaction was mined in. Returned when confirming. The market's rate and term offering, read back from the chain after the transaction. Rates, penalties and ratios are basis-point strings, durations are seconds, and dates are unix seconds. A part that could not be read is left out. Returned when confirming. `CURVE`, `CLAMPED` or `FIXED`. Clamp floor, or the fixed rate under `FIXED`. Clamp cap, or the fixed rate under `FIXED`. Fixed-rate ceiling, or `null` when none is recorded. Maximum loan duration in seconds. `"0"` when unset. Grace period in seconds. Terminal due date, or `null`. Market due floor, or `null`. Term penalty. Whether the extension flow is switched on. Reserve ratio. The operator's share of repaid interest after the infrastructure fee. The external price feed. Present only on a market whose `priceSource` is `ORACLE`. Names of the stored market fields this confirmation changed. Empty when the record already matched the chain. Returned when confirming. ```bash cURL theme={null} curl -X POST "https://api.trusset.org/lending-external-securities-v2/api/markets/{marketId}/rate-mode" \ -H "X-API-Key: trusset_your_key_here" \ -H "Content-Type: application/json" \ -d '{ "rateMode": "CLAMPED", "rateFloorBps": 300, "rateCapBps": 1200 }' ``` ```typescript TypeScript theme={null} const url = `https://api.trusset.org/lending-external-securities-v2/api/markets/${marketId}/rate-mode`; const headers = { 'X-API-Key': 'trusset_your_key_here', 'Content-Type': 'application/json' }; const build = await fetch(url, { method: 'POST', headers, body: JSON.stringify({ rateMode: 'FIXED', fixedRateBps: 800 }) }); const { data: calldata } = await build.json(); const tx = await ownerWallet.sendTransaction({ to: calldata.to, data: calldata.data, value: calldata.value, chainId: calldata.chainId }); await tx.wait(); const confirm = await fetch(url, { method: 'POST', headers, body: JSON.stringify({ txHash: tx.hash }) }); const { data } = await confirm.json(); ``` ```json Calldata Response theme={null} { "success": true, "data": { "action": "SIGN_TRANSACTION", "transaction": { "to": "0x3b25752c1459c5cf1b0bfcfdf0d56883c8047423", "data": "0x..." }, "to": "0x3b25752c1459c5cf1b0bfcfdf0d56883c8047423", "data": "0x...", "functionName": "setRateMode", "requiredRole": "INTEREST_MODEL_OWNER", "requiredSigner": "0x5ad87a0621175206b72d10e4b8577b192e7f40ab", "heldByThisInstance": true, "signerAddress": "0x5ad87a0621175206b72d10e4b8577b192e7f40ab", "note": null, "confirmWith": { "endpoint": "POST /lending-external-securities-v2/api/markets/clx_secmarket_001/rate-mode", "field": "txHash" }, "chainId": 11155111, "value": "0" } } ``` ```json Confirmed Response theme={null} { "success": true, "data": { "txHash": "0x9f2c41d8b7e05a3164c2870fbd935e1a4c7802db6135ea9048f7c21b5d3ea41b", "functionName": "setRateMode", "signedBy": "0x5ad87a0621175206b72d10e4b8577b192e7f40ab", "blockNumber": 6789012, "offering": { "maxLoanDuration": "15552000", "termGracePeriod": "259200", "terminalDueDate": null, "termPenalty": "200", "marketDueFloor": null, "allowExtension": false, "rateMode": "CLAMPED", "rateFloor": "300", "rateCap": "1200", "maxFixedRate": "1500", "reserveRatio": "500", "operatorShare": "800" }, "updatedColumns": ["rateMode", "rateFloor", "rateCap"] } } ``` ```json Error - Fixed Rate Needs Terms theme={null} { "success": false, "error": { "code": "FIXED_RATE_REQUIRES_TERMS", "message": "The model refuses FIXED mode while the market has no loan terms: set a term configuration first, so the term clock replaces the curve as the repayment pull." } } ``` ## Error Codes | Code | HTTP | Cause | | --------------------------- | ----- | ----------------------------------------------------------------------------------------------------------------------------------------------- | | `MISSING_MARKET_ID` | `400` | The `marketId` path segment is longer than 100 characters | | `VALIDATION_ERROR` | `400` | A field is outside its range, a bound belongs to another mode, a bound the mode requires is missing, or `txHash` is malformed | | `INVALID_RATE_OFFERING` | `400` | `rateFloorBps` exceeds `rateCapBps` | | `RATE_ABOVE_MAX_FIXED` | `400` | `fixedRateBps` exceeds the market's fixed-rate ceiling | | `INVALID_CONFIRMATION` | `400` | The market has no on-chain address, so there is nothing to confirm against | | `MARKET_NOT_FOUND` | `404` | No market with this ID on your instance | | `FIXED_RATE_REQUIRES_TERMS` | `409` | `FIXED` was requested on a market with no maximum loan duration | | `MARKET_PENDING_CURATOR` | `409` | The market has no lender of record yet, so the market itself still owns the model and no wallet can sign. Skipped when confirming with `txHash` | | `INTERNAL_ERROR` | `500` | The chain could not be read while confirming. Retry shortly | | `MARKET_STATE_UNAVAILABLE` | `503` | The market's term configuration could not be read to check a switch to `FIXED`. Retry shortly | | `MODEL_UNRESOLVED` | `503` | The market's interest model address could not be resolved. Retry shortly | Confirming with `txHash` can also return any [transaction verification error](/endpoints/introduction#confirm-a-transaction).