{"uid":"cap_ygYxgPxDQsuP3efJ-SVwQ","slug":"xynaptic-fiat-usdc-rate-48b5fe40","name":"Xynaptic Fiat-USDC Rate","description":"Xynaptic Fiat-USDC Rate — best fiat↔USDC conversion rate per payment rail (Base, Polygon, Solana): live Coinbase spot EUR/USD with bid-ask spread, estimated network fees, slippage hint and best-rail verdict for agents settling in USDC. GET (?currency=EUR).","url":"https://api.xynaptic.io/v1/fiat-usdc-rate?utm_source=zero.xyz","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","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","additionalProperties":{"type":"string"}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.02","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":"$0.02/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.02","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_IBlFQvcF8o3Q4rGpBrvma","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.02","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the best fiat-to-USDC conversion rate across Base, Polygon, and Solana payment rails, including live Coinbase spot price, bid-ask spread, network fees, slippage hint, and a best-rail verdict.","exampleAgentPrompt":"What's the best rate and cheapest rail to convert EUR to USDC right now — show me the live Coinbase spot price, estimated fees, and whether I should use Base, Polygon, or Solana?","exampleUseCases":[{"title":"Cheapest rail for EUR settlement","prompt":"I need to settle a payment in USDC from euros — can you check live rates and tell me whether Base, Polygon, or Solana gives me the best deal including network fees and slippage?"},{"title":"Pre-trade FX rate check for agent","prompt":"Before my agent executes a USDC payout, pull the current EUR to USDC conversion rate with the bid-ask spread and flag which payment rail has the lowest cost right now."},{"title":"Monitor EUR-USDC rate for arbitrage","prompt":"What's the current Coinbase spot EUR/USDC rate and how does the slippage and fee compare across Base, Polygon, and Solana — I want to know the best-rail verdict before I move funds."}],"resultDescription":"Returns the live Coinbase spot EUR/USD price, bid-ask spread, estimated network fees per rail (Base, Polygon, Solana), a slippage hint, and a best-rail verdict recommending which network to use for the most cost-effective USDC settlement.","failureModes":["Unsupported currency code returns an error or empty result","Coinbase spot feed unavailable causes stale or missing rate","Network fee estimation may lag real-time congestion","Missing or invalid query parameter returns 400-level error","Rate limiting may apply if called too frequently"],"whenToPreferThis":"Use this endpoint when an agent needs to programmatically determine the optimal payment rail and current cost to convert fiat (e.g. EUR) to USDC before executing an on-chain settlement. Preferred over generic FX APIs because it bundles cross-rail fee comparison and a concrete best-rail recommendation specifically for USDC stablecoin settlement on Base, Polygon, and Solana.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T12:36:11.264Z","isFirstParty":false,"canonicalSlug":"xynaptic-fiat-usdc-rate-48b5fe40"}