{"uid":"cap_qENtz9EXB1mONeh2SlF1M","slug":"apexapi-ai-similarity-595b360c","name":"ApexAPI AI Similarity","description":"Crypto, AI, Social Media, Finance, Weather, Tools & more. Pay per call in USDC on Base. No API keys.","url":"https://apex-api-gamma.vercel.app/api/ai/similarity","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"query":{"type":"string","description":"Search query or input parameter"}}},"responseSchema":{"type":"object","description":"API response data"},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.097567","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":"$0.097567/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.097567","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.097567","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_R0z29go96tAahMJPaQx1X","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.097567","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Computes semantic similarity between a query string and reference content using AI embedding models","exampleAgentPrompt":"How semantically similar are these two sentences: 'The stock market crashed today' and 'Equities fell sharply this morning'? Give me a similarity score.","exampleUseCases":null,"resultDescription":"Returns a similarity score or relevance metric indicating how semantically close the input query is to reference content, likely as a float between 0 and 1 or a ranked list.","failureModes":["Empty or missing query field returns a 400 validation error","Query too long may exceed token limits causing a 422 error","Payment not attached or insufficient USDC causes a 402 response","Model backend unavailable triggers a 503 or timeout","Malformed JSON body returns a 400 parse error"],"whenToPreferThis":"Use this endpoint when you need pay-per-call semantic similarity scoring with no API key setup, billed in USDC on Base. Ideal for agents that need lightweight, on-demand text similarity without managing embedding model credentials.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T18:32:34.655Z","isFirstParty":false}