fix: swap

src/lib/jupiter.ts

@@ -11,6 +11,13 @@ const USDC_MINT = 'EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v'
 const USDT_MINT = 'Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB'
 const SOL_MINT = 'So11111111111111111111111111111111111111112'
 
+/** 稳定币 mint：用 USDC 换这些币时无需 swap */
+const STABLECOIN_MINTS = [
+	USDC_MINT,
+	USDT_MINT,
+	'USD1ttGY1N17NEEHLmELoaybftRBUSErhqYiQzvEmuB', // USD1
+]
+
 export interface JupiterQuote {
 	inputMint: string
 	inAmount: string
@@ -174,6 +181,16 @@ export async function swapIfNeeded(
 		return { success: true }
 	}
 
+	const mint = String(outputMint ?? '').trim()
+	const isStablecoin =
+		STABLECOIN_MINTS.includes(mint) || mint === USDC_MINT
+	if (isStablecoin) {
+		console.log(
+			`Skip swap: output is stablecoin (USDC/USDT), no need to swap USDC -> same`
+		)
+		return { success: true }
+	}
+
 	const inputAmountRaw = Math.floor(Number(usdValue) * 1e6)
 	if (inputAmountRaw < 1e6) {
 		console.log(`Skip swap: USD value too small (${usdValue})`)