{"uid":"cap_esU0Bs0yzkcJeMQ0cpFU0","slug":"op-mainnet-dex-slippage-price-impact-estimator-b1b138cd","name":"OP Mainnet DEX Slippage & Price Impact Estimator","description":"What a trade size actually executes at on OP Mainnet, simulated against live reserves. Returns best (venue, amountOut, executionPrice, priceImpactBps, feeBps, totalCostBps), routingGain, venues[]. Requires ?pair=SYM/SYM AND ?amountUsd=25000 (or ?amountIn=). pair alone = 400 missing_amount. Errors: 400 bad_pair|missing_amount|bad_amount, 404 no_pools|no_quote|cannot_size_in_usd, 502 upstream_read_failed. Spot price without a size is /price. Chain-pinned; bare /slippage = BSC.","url":"https://x402.donnyautomation.com/optimism/slippage","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET"],"type":"string"},"queryParams":{"type":"object","required":["pair","amountUsd"],"properties":{"pair":{"type":"string","description":"Token pair as SYM/SYM on OP Mainnet (e.g. WETH/USDC)."},"amountIn":{"type":"string","description":"Trade size denominated in the FIRST pair symbol instead of USD. An alternative to amountUsd; supplying either one is enough."},"amountUsd":{"type":"string","description":"Trade size in USD, e.g. 10000. Required unless amountIn is given instead."}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"ts":"2026-07-31T00:00:00.000Z","chainId":10,"network":"optimism"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.01","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"probe","requiresHandshake":false,"reviewCount":0,"rating":{"score":"0.00","successRate":"0.00","reviews":0,"stars":null,"state":"unrated"},"availabilityStatus":"unknown","priceObserved":null,"sessionDeposit":null,"pricing":{"kind":"static","summary":"$0.01/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.01","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_omahHccQBxOpAOlzPas9q","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.01","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Simulates a swap on Optimism (OP Mainnet) against live AMM reserves across SushiSwap and Uniswap v3 fee tiers to return the best execution venue, expected amount out, price impact in basis points, pool fee, and routing savings.","exampleAgentPrompt":"Before I execute my trade, check what slippage and price impact I'll actually get swapping WETH for USDC on Optimism — run it against SushiSwap and Uniswap v3 pools and tell me the best venue and exact amount out.","exampleUseCases":[{"title":"Pre-trade slippage check for trading bot","prompt":"Before my bot executes the WETH/USDC swap on Optimism, simulate the trade and tell me the price impact in basis points and what I'll actually receive, not just the spot price."},{"title":"DEX routing decision on OP Mainnet","prompt":"I want to swap OP/USDC on Optimism — check SushiSwap and all Uniswap v3 fee tiers and tell me which venue gives the best execution and how much I save by routing correctly."},{"title":"Slippage monitoring for DEX aggregator","prompt":"My aggregator needs a pre-trade check for a WETH/OP pair on Optimism — simulate the swap against live pool reserves and return the price impact and best amount out across all venues."}],"resultDescription":"Returns the best execution venue (SushiSwap or Uniswap v3 fee tier), expected amount out for the trade, price impact expressed in basis points, the pool fee, and the savings achieved by optimal routing versus simply taking the best quoted spot price — all computed against live on-chain reserves on OP Mainnet.","failureModes":["Invalid or unsupported token pair symbol returns an error (e.g. unrecognized ticker)","Token pair with no live liquidity on OP Mainnet returns empty or null execution data","Network or RPC issues reading live OP Mainnet reserves may cause stale or failed responses","Missing required 'pair' query parameter returns a 400 validation error","Payment not completed (x402) results in a 402 Payment Required response before data is returned"],"whenToPreferThis":"Use this endpoint when you need pre-trade execution simulation specifically on Optimism (OP Mainnet) and want to compare SushiSwap against multiple Uniswap v3 fee tiers simultaneously. Prefer it over generic spot price APIs when actual trade size matters and you need price impact in basis points, not just a reference price. It is ideal for trading bots, DEX aggregators, or smart order routing systems operating on Optimism that need to validate execution quality before submitting an on-chain transaction.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T12:56:27.977Z","isFirstParty":false}