Previews

Read-only quote computations — fees, exit fees, TP/SL PnL, margin.

POST endpoints that compute numbers without building a transaction. Each returns { "err": "…" } in the body when the computation fails. Shared conventions: Conventions. Task walkthrough: Preview fees & PnL.

Method	Path
POST	/preview/limit-order-fees
POST	/preview/exit-fee
POST	/preview/tp-sl
POST	/preview/margin

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Limit-order fees

POST /preview/limit-order-fees

Entry price, entry fee, liquidation price, and borrow rate for a would-be position.

Field	Type	Req	Description
marketSymbol	string	✓	Market token symbol
inputAmountUi	string	✓	Collateral amount (UI)
outputAmountUi	string	✓	Size in target token (UI)
side	enum	✓	LONG / SHORT
limitPrice	string	—	Limit price (UI); uses live price if omitted

Response: { entryPriceUi, entryFeeUsdUi, liquidationPriceUi, borrowRateUi }.

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Exit fee

POST /preview/exit-fee

Exit fee and exit price for closing (part of) a position.

Field	Type	Req	Description
marketSymbol	string	✓	Market token symbol
side	enum	✓	LONG / SHORT
closeAmountUsdUi	string	✓	USD to close (UI)
owner	string	✓	Owner wallet pubkey

Response: { exitFeeUsdUi, exitFeeAmountUi, exitPriceUi }.

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TP/SL

POST /preview/tp-sl

mode selects the computation: forward (trigger price → PnL), reverse_pnl (target PnL → trigger price), reverse_roi (target ROI% → trigger price).

Supply owner to use the caller's existing position; omit it and pass the inline fields to preview before a position exists.

Field	Type	Req	Description
mode	string	✓	forward / reverse_pnl / reverse_roi
marketSymbol	string	✓	Market token symbol
side	enum	✓	LONG / SHORT
owner	string	—	Owner pubkey (owner-position mode)
entryPriceUi	string	—	Entry price (inline mode)
sizeUsdUi	string	—	Position size, USD (inline mode)
collateralUsdUi	string	—	Collateral, USD (inline mode)
triggerPriceUi	string	—	Forward: trigger price to price PnL for
targetPnlUsdUi	string	—	Reverse-PnL: target PnL, USD
targetRoiPercent	number	—	Reverse-ROI: target ROI %

Response: { pnlUsdUi?, pnlPercentage?, triggerPriceUi?, maxProfitPriceUi? } — forward returns pnlUsdUi/pnlPercentage; reverse modes return triggerPriceUi.

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Margin

POST /preview/margin

Preview a collateral add/remove on an existing position.

Field	Type	Req	Description
marketSymbol	string	✓	Market token symbol
side	enum	✓	LONG / SHORT
marginDeltaUsdUi	string	✓	Margin delta, USD (UI)
action	enum	✓	ADD / REMOVE
owner	string	✓	Owner wallet pubkey

Response: { newLeverageUi, newLiquidationPriceUi, maxAmountUsdUi, existingCollateralUsdUi?, newCollateralUsdUi?, existingLeverageUi?, existingLiquidationPriceUi?, deltaUsdUi? }.