{"uid":"cap_HdK9rCYdCziG87JNpOzRh","slug":"graph-advocate-kalshi-polymarket-spread-finder-c480b6dc","name":"Graph Advocate Kalshi-Polymarket Spread Finder","description":"Cross-source arbitrage spread between Kalshi and Polymarket on a topic. POST {topic, limit?}. Pulls matching markets from both venues (Politics + Elections overlap heavily), computes price mid-spread + arbitrage direction. JOIN that single-source passthrough APIs (incl. Pinax Token API) structurally can't return — this is what survives Pinax shipping Kalshi support later.","url":"https://graphadvocate.com/kalshi-polymarket/spread","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"limit":{"type":"integer","default":5,"maximum":10,"minimum":1},"topic":{"type":"string"}}},"responseSchema":{"type":"json","example":{"pairs":[{"spread_bps":400,"kalshi_ticker":"KXFED-25DEC-CUT25","kalshi_yes_mid":0.62,"polymarket_yes_mid":0.58,"arbitrage_direction":"long-poly-short-kalshi","polymarket_market_slug":"fed-rate-cut-december","spread_yes_kalshi_minus_poly":0.04}],"topic_keyword":"fed rate","kalshi_candidates":3,"polymarket_candidates":2}},"example":{"request":{"topic":"fed rate cut"},"response":{"pairs":[],"status":"no_matches","sources":{"kalshi":"https://api.elections.kalshi.com/trade-api/v2","polymarket":"token-api proxy"},"agent_note":"No markets on either Kalshi or Polymarket matched 'fed rate cut'. Sample active markets shown above — pick a keyword that appears in one of their titles. Common high-volume topics: fed rate, super bowl, presidential, btc price, world cup, oscars.","did_you_mean":{"kalshi_active":[{"title":"yes Canada,yes Ecuador,yes Germany,yes Spain,yes Argentina,yes France,yes Norway","ticker":"KXMVESPORTSMULTIGAMEEXTENDED-S20264E30A0B9832-33ABD2C57B8"},{"title":"yes England,yes Portugal,yes Colombia,yes Mexico,yes Switzerland,yes Brazil,yes ","ticker":"KXMVESPORTSMULTIGAMEEXTENDED-S20268C9027D7BDC-9B5128D7208"},{"title":"yes Jalen Brunson: 2+,yes OG Anunoby: 2+,yes Julian Champagnie: 2+,yes Victor We","ticker":"KXMVESPORTSMULTIGAMEEXTENDED-S2026AB0774645CF-7602EBB434E"},{"title":"yes Taylor Fritz,yes Bo Nickal,yes Sean O'Malley,yes Ilia Topuria","ticker":"KXMVESPORTSMULTIGAMEEXTENDED-S202627608884011-A6FD0378D12"},{"title":"yes San Antonio,yes Jalen Brunson: 25+,yes Karl-Anthony Towns: 10+,yes OG Anunob","ticker":"KXMVESPORTSMULTIGAMEEXTENDED-S202621ABDDED551-1CC1F40E1BE"}],"polymarket_active":[{"slug":"will-donald-trump-win-the-2024-us-presidential-election","question":"Will Donald Trump win the 2024 US Presidential Election?"},{"slug":"will-kamala-harris-win-the-2024-us-presidential-election","question":"Will Kamala Harris win the 2024 US Presidential Election?"},{"slug":"will-donald-trump-be-inaugurated","question":"Will Donald Trump be inaugurated?"},{"slug":"will-the-sacramento-kings-win-the-2025-nba-finals","question":"Will the Sacramento Kings win the 2025 NBA Finals?"},{"slug":"will-nicolae-ciuca-win-the-2024-romanian-presidential-election","question":"Will Nicolae Ciucă win the 2024 Romanian Presidential election?"}]},"topic_keyword":"fed rate cut","kalshi_candidates":0,"polymarket_candidates":0}},"exampleRequest":{"topic":"fed rate cut"},"tags":["x402"],"displayCostAmount":"0.05","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"settled","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":"$0.05/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.05","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.05","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_MMfbZ_6ututiGmV0B0JR4","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.05","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Compares Kalshi and Polymarket odds on a given topic to surface arbitrage spreads and directional trade signals between the two prediction markets.","exampleAgentPrompt":"Show me the current spread between Kalshi and Polymarket on 'fed rate cut' — I want to see the basis points, which direction to trade, and which specific tickers are involved.","exampleUseCases":null,"resultDescription":"Returns a list of matched market pairs with: spread in basis points, Kalshi yes mid price, Polymarket yes mid price, arbitrage direction (e.g. long-poly-short-kalshi), Kalshi ticker symbol, Polymarket market slug, plus counts of candidate markets found on each platform for the given topic keyword.","failureModes":["No matching markets found on one or both platforms for the given topic keyword — returns empty pairs array","Ambiguous topic keyword matches too many unrelated markets — results may be noisy or mismatched","Kalshi or Polymarket data temporarily unavailable — stale or partial results","Rate limit exceeded on free tier (3 queries/day) — requires $0.05 USDC payment via x402 on Base","Payment not confirmed on Base — request blocked until transaction settles"],"whenToPreferThis":"Use this endpoint when you need a direct side-by-side price comparison between Kalshi and Polymarket on the same real-world event and want to identify arbitrage or directional trade opportunities expressed as a spread in basis points. Prefer this over general prediction market APIs when you specifically need cross-platform spread data and actionable trade direction signals.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T06:37:35.413Z","isFirstParty":false}