{"uid":"cap_j3mUx01uCTX_X_VNvn0vC","slug":"speraxos-fear-greed-index-api-511624ec","name":"SperaxOS Fear & Greed Index API","description":"AI-powered DeFi intelligence APIs payable via the x402 HTTP payment protocol. No API key required — pay per request with USDC on Base. Identity-only (SIWX) endpoints are free for wallets with an agentcash identity.","url":"https://chat.sperax.io/api/x402/fear-greed","method":"GET","headers":{},"bodySchema":{"type":"object","properties":{"limit":{"type":"integer","description":"Number of historical data points (default: 1, max: 30)"}}},"responseSchema":{"type":"object","properties":{"data":{"type":"array","items":{"type":"object","properties":{"value":{"type":"string","example":"72"},"timestamp":{"type":"string","example":"1712524800"},"value_classification":{"type":"string","example":"Greed"}}}},"name":{"type":"string","example":"Fear and Greed Index"},"metadata":{"type":"object","properties":{"error":{"type":"string","nullable":true}}}}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.001","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":"$0.001/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.001","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_wl2NIiW-XBADd18UHTxVd","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.001","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns the current and historical Crypto Fear & Greed Index value and classification, payable per-request with USDC via x402.","exampleAgentPrompt":"What is the current crypto fear and greed index, and can you show me the last 7 days of readings so I can see how sentiment has shifted?","exampleUseCases":[{"title":"Daily crypto sentiment check","prompt":"What's the crypto fear and greed index right now — is the market in fear or greed territory today?"},{"title":"Historical sentiment trend review","prompt":"Pull the last 30 days of the crypto fear and greed index so I can see how market sentiment has trended over the past month."},{"title":"Automated DeFi strategy signal","prompt":"Check the current fear and greed index value and tell me if it's in Extreme Fear, Fear, Neutral, Greed, or Extreme Greed — I want to use it to decide whether to rebalance my DeFi portfolio."}],"resultDescription":"Returns a JSON array of data points each containing a numeric index value (0-100), a human-readable classification string (e.g. 'Extreme Fear', 'Fear', 'Neutral', 'Greed', 'Extreme Greed'), and a Unix timestamp. Also returns the index name and any error metadata.","failureModes":["Payment not included or insufficient USDC — returns 402 Payment Required","limit parameter exceeds maximum of 30 — may return error or truncated data","Network or upstream data source unavailable — metadata.error field will be populated","Invalid limit type (non-integer) — request may be rejected with a 400 error"],"whenToPreferThis":"Choose this endpoint when you need real-time or recent historical Crypto Fear & Greed Index data without managing API keys, and you are already operating in an x402 USDC payment-capable environment on Base. Ideal for DeFi agents, trading bots, or portfolio management tools that need a quick sentiment signal payable programmatically per call.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T06:30:35.255Z","isFirstParty":false}