Jupiter swap quote

---
name: jupiter-quote
description: Get a live Jupiter swap quote on Solana - output amount, minimum received after slippage, price impact and the route through each DEX. Accepts SOL, USDC, USDT or any mint address and human amounts like 2.5. Use when the user asks how much they would get for a swap, or to compare a price before trading. Quote only - it never builds, signs or sends a transaction.
---

# Jupiter swap quote

Read-only, free, no API key, no wallet. It asks Jupiter what a swap would return right now.

## Run

```bash
node scripts/quote.mjs <from> <to> <amount> [--slippage-bps 50]
node scripts/quote.mjs SOL USDC 2.5
node scripts/quote.mjs USDC JUPyiwrYJFskUPiHa7hkeR8VUtAeFoSYbKedZNsDvCN 100 --slippage-bps 100
```

`<from>` and `<to>` are `SOL`, `USDC`, `USDT` or a mint address. `<amount>` is in whole tokens
(2.5 SOL, not lamports). Slippage is in basis points: 50 = 0.5%, max 1000.

## Output

JSON on stdout: `{ input: { mint, symbol, amount }, output: { mint, symbol, amount, minimum },
slippageBps, priceImpactPct, price, route: [ { dex, percent } ], contextSlot }`.

## Notes for the agent

- A quote is a snapshot: it changes every few seconds. Show the time with it.
- Mention the price impact when it is above 1%.
- This skill cannot execute the swap. If the user wants to trade, tell them to use a wallet or
  app they trust.

{
  "slug": "jupiter-quote",
  "name": "Jupiter swap quote",
  "spine": "Swap quote",
  "summary": "Quotes a Solana token swap through Jupiter: how much you get out, the minimum after slippage, price impact and the route. Quote only, never signs or sends.",
  "job": "Quote a Jupiter swap",
  "category": "swaps",
  "chains": ["solana"],
  "version": "1.0.0",
  "author": "Shelfwise",
  "license": "MIT",
  "price": { "type": "free" },
  "entry": "scripts/quote.mjs",
  "runtime": "Node 18+ or Bun, no dependencies",
  "permissions": {
    "network": ["lite-api.jup.ag"],
    "keys": [],
    "env": [],
    "wallet": "none",
    "filesystem": "none"
  },
  "sources": [
    { "name": "Jupiter Swap API: quote", "url": "https://dev.jup.ag/docs/swap-api/get-quote" },
    { "name": "Jupiter Tokens API v2", "url": "https://dev.jup.ag/docs/token-api/v2" }
  ],
  "ask": "How much USDC would I get for 2.5 SOL on Jupiter right now?"
}

MIT License

Copyright (c) 2026 Shelfwise

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

// Jupiter swap quote: read-only quote with human amounts. Zero dependencies.
import { pathToFileURL } from "node:url";

const API = "https://lite-api.jup.ag";
const KNOWN = {
  SOL: { mint: "So11111111111111111111111111111111111111112", symbol: "SOL", decimals: 9 },
  USDC: { mint: "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v", symbol: "USDC", decimals: 6 },
  USDT: { mint: "Es9vMFrzaCERmJfrF4H2FYD4KCoNkY11McCe8BenwNYB", symbol: "USDT", decimals: 6 },
};
const MINT_RE = /^[1-9A-HJ-NP-Za-km-z]{32,44}$/;

async function getJson(url) {
  const res = await fetch(url, { headers: { accept: "application/json" } });
  const body = await res.json().catch(() => null);
  if (!res.ok) throw new Error(body?.error ?? `Jupiter answered ${res.status}`);
  return body;
}

export async function resolveToken(input) {
  const upper = String(input ?? "").toUpperCase();
  if (KNOWN[upper]) return KNOWN[upper];
  const known = Object.values(KNOWN).find((k) => k.mint === input);
  if (known) return known;
  if (!MINT_RE.test(String(input ?? ""))) throw new Error(`Unknown token "${input}": use SOL, USDC, USDT or a mint address`);
  const list = await getJson(`${API}/tokens/v2/search?query=${input}`);
  const t = (Array.isArray(list) ? list : []).find((x) => x?.id === input);
  if (!t || !Number.isInteger(t.decimals)) throw new Error(`Jupiter does not know mint ${input}`);
  return { mint: t.id, symbol: t.symbol ?? null, decimals: t.decimals };
}

// Whole-token string -> integer base units, without floating point drift.
export function toBaseUnits(amount, decimals) {
  const s = String(amount).trim();
  if (!/^\d+(\.\d+)?$/.test(s)) throw new Error(`Invalid amount "${amount}"`);
  const [whole, frac = ""] = s.split(".");
  const units = BigInt(whole + frac.padEnd(decimals, "0").slice(0, decimals));
  if (units <= 0n) throw new Error("Amount must be above zero");
  return units;
}

export function fromBaseUnits(units, decimals) {
  const s = BigInt(units).toString().padStart(decimals + 1, "0");
  const whole = s.slice(0, s.length - decimals);
  const frac = s.slice(s.length - decimals).replace(/0+$/, "");
  return Number(frac ? `${whole}.${frac}` : whole);
}

export async function quote(from, to, amount, { slippageBps = 50 } = {}) {
  if (!from || !to || amount === undefined) throw new Error("Usage: quote.mjs <from> <to> <amount> [--slippage-bps 50]");
  slippageBps = Math.max(0, Math.min(1000, Math.round(Number(slippageBps) || 0)));
  const a = await resolveToken(from);
  const b = await resolveToken(to);
  if (a.mint === b.mint) throw new Error("From and to are the same token");
  const units = toBaseUnits(amount, a.decimals);
  const q = await getJson(
    `${API}/swap/v1/quote?inputMint=${a.mint}&outputMint=${b.mint}&amount=${units}&slippageBps=${slippageBps}`,
  );
  const outAmount = fromBaseUnits(q.outAmount, b.decimals);
  const inAmount = fromBaseUnits(q.inAmount, a.decimals);
  return {
    source: "jupiter",
    fetchedAt: new Date().toISOString(),
    input: { mint: a.mint, symbol: a.symbol, amount: inAmount },
    output: { mint: b.mint, symbol: b.symbol, amount: outAmount, minimum: fromBaseUnits(q.otherAmountThreshold, b.decimals) },
    slippageBps,
    priceImpactPct: Number(q.priceImpactPct) * 100,
    price: inAmount > 0 ? outAmount / inAmount : null,
    route: (q.routePlan ?? []).map((r) => ({ dex: r?.swapInfo?.label ?? "unknown", percent: r?.percent ?? null })),
    contextSlot: q.contextSlot ?? null,
  };
}

if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href) {
  const args = process.argv.slice(2);
  const i = args.indexOf("--slippage-bps");
  const slippageBps = i >= 0 ? Number(args[i + 1]) : 50;
  if (i >= 0) args.splice(i, 2);
  quote(args[0], args[1], args[2], { slippageBps })
    .then((r) => console.log(JSON.stringify(r, null, 2)))
    .catch((e) => {
      console.log(JSON.stringify({ error: String(e?.message ?? e) }));
      process.exit(1);
    });
}

// Self-test: a live 1 SOL -> USDC quote plus offline checks of the amount maths. Run: node test.mjs
import { pathToFileURL } from "node:url";
import { quote, toBaseUnits, fromBaseUnits } from "./scripts/quote.mjs";

export default async function test() {
  const checks = [];
  const check = (name, ok) => checks.push({ name, ok: Boolean(ok) });
  check("converts 2.5 SOL to lamports", toBaseUnits("2.5", 9) === 2500000000n);
  check("converts base units back", fromBaseUnits("1234500", 6) === 1.2345);
  const r = await quote("SOL", "USDC", "1", { slippageBps: 50 });
  check("quotes a positive USDC amount", r.output.amount > 0);
  check("minimum is at most the quote", r.output.minimum <= r.output.amount);
  check("has a route", r.route.length > 0);
  check("price impact is a number", Number.isFinite(r.priceImpactPct));
  let rejected = false;
  try { await quote("SOL", "SOL", "1"); } catch { rejected = true; }
  check("rejects a same-token swap", rejected);
  return { ok: checks.every((c) => c.ok), checks };
}

if (process.argv[1] && import.meta.url === pathToFileURL(process.argv[1]).href) {
  test().then((r) => { console.log(JSON.stringify(r, null, 2)); process.exit(r.ok ? 0 : 1); },
    (e) => { console.log(JSON.stringify({ ok: false, error: String(e?.message ?? e) })); process.exit(1); });
}