{"uid":"cap_7pF6nf03DBn1mVxowWe4M","slug":"bookproof-polymarket-market-health-order-book-intelligence-6d1131d9","name":"Bookproof — Polymarket Market Health & Order Book Intelligence","description":"Read-only Polymarket depth, spread, fee, freshness, and executable VWAP data for autonomous agents, paid per call with x402.","url":"https://bookproof-api.sn95wjq846.chatgpt.site/api/v1/market-health","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"},"pathParams":{"type":"object"},"queryParams":{"type":"object","required":["market"],"properties":{"market":{"type":"string","maxLength":500,"minLength":2,"description":"Polymarket URL, market slug, CLOB token ID, or market search phrase."}},"additionalProperties":false}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"fee":{"exponent":1,"takerOnly":true,"takerRate":0.04},"books":[{"spread":0.01,"bestAsk":0.43,"bestBid":0.42,"outcome":"Yes","imbalance2c":-0.12}],"health":{"stale":false,"status":"healthy","crossed":false},"market":{"slug":"will-the-fed-decrease-interest-rates-by-25-bps-after-the-july-2026-meeting"},"service":"bookproof"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.005","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":"$0.005/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.005","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_ydgzgtdadt8gE3o67Hb5-","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.005","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns real-time Polymarket order book depth, spread, fees, freshness, and executable VWAP data for a given prediction market.","exampleAgentPrompt":"Check the Polymarket order book health for the 'will-the-fed-decrease-interest-rates-by-25-bps-after-the-july-2026-meeting' market — I need the current spread, best bid and ask, taker fee rate, and whether the book is fresh and not crossed before I place a trade.","exampleUseCases":[{"title":"Pre-trade liquidity check for prediction market","prompt":"Before I trade on Polymarket, check the order book for the 'will-trump-win-the-2026-midterms' market — I need to know the best bid and ask, the spread, whether the book is healthy, and what taker fees I'll be charged."},{"title":"Automated trading bot market health monitor","prompt":"Every minute, pull the market health and spread data for Polymarket's 'will-btc-hit-100k-by-end-of-2025' market and alert me if the book goes stale, crossed, or if the spread widens beyond 3 cents."},{"title":"Fee-aware execution cost estimation","prompt":"I'm about to execute a large trade on Polymarket — can you pull the current order book imbalance, VWAP, and taker fee rate for the 'will-the-fed-decrease-interest-rates-by-25-bps-after-the-july-2026-meeting' market so I can estimate my total execution cost?"}],"resultDescription":"Returns a JSON object containing: the market slug, per-outcome order book data (best bid, best ask, spread, 2-cent imbalance), fee parameters (taker rate, exponent, taker-only flag), and a health object indicating whether the book is stale, crossed, or healthy.","failureModes":["Market not found: invalid slug, URL, or token ID returns an error or empty result","Stale data: health.stale=true indicates the order book hasn't been updated recently","Crossed book: health.crossed=true means best bid >= best ask, making execution unreliable","Payment failure: missing or invalid x402 payment header results in 402 response","Rate limiting: excessive calls without valid payment may be throttled","Ambiguous search phrase: non-unique market search phrase may resolve to wrong market"],"whenToPreferThis":"Use this endpoint when an autonomous agent needs pre-trade intelligence on Polymarket — specifically when fee-aware execution cost, spread, order book freshness, and health checks are required before placing or sizing a trade. Prefer this over generic Polymarket API calls when you need VWAP, imbalance, and fee data in a single response, or when you need to verify that the book is not crossed or stale before committing capital.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T12:36:52.524Z","isFirstParty":false}