{"uid":"cap_3rZgy0Y4hJ2rcDv8AkxsO","slug":"synapse-keywords-api-5c222598","name":"Synapse Keywords API","description":"Public data and utility APIs paid per call in USDC on Base (x402). No accounts, no API keys. 174 routes: crypto/equity data, onchain reads, DNS/email/security intel, geo/weather, x402 payment diagnostics, dev utilities and more.","url":"https://anibalb.duckdns.org/x402/keywords?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","properties":{}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":{"type":"json","example":{"keywords":[{"score":3,"keyword":"bitcoin"},{"score":1,"keyword":"digital"}]}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.002","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":"$0.002/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.002","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_rHIYDEPZ8eE4xnSE7DOCp","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.002","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns a ranked list of keywords extracted from a given context, each with a relevance score","exampleAgentPrompt":"Can you hit the Synapse keywords endpoint and get me a ranked list of keywords with their relevance scores?","exampleUseCases":[{"title":"Tag generation for blog content","prompt":"I just wrote a blog post about Bitcoin and digital assets — can you extract the top keywords with relevance scores so I can use them as tags?"},{"title":"SEO keyword discovery","prompt":"Pull the ranked keywords from the Synapse keywords API so I can see which terms have the highest scores for my content strategy."},{"title":"Topic modeling for news articles","prompt":"I need to identify the most important keywords and their weights from this content — can you run it through the Synapse keywords extractor?"}],"resultDescription":"A JSON array of keyword objects, each containing a 'keyword' string and an integer 'score' representing relevance (e.g. [{\"score\":3,\"keyword\":\"bitcoin\"},{\"score\":1,\"keyword\":\"digital\"}]).","failureModes":["Missing required 'input' field returns validation error","Unsupported HTTP method (e.g. POST) returns 405","Payment failure or insufficient USDC balance returns 402","Service unavailable on DuckDNS host returns 502 or timeout","Empty or malformed query returns empty keyword array"],"whenToPreferThis":"Choose this endpoint when you need lightweight, pay-per-call keyword extraction without account setup or API keys, especially in x402/USDC payment contexts on Base. Ideal for agents that need keyword scoring on demand without committing to a subscription NLP service.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-31T18:42:08.459Z","isFirstParty":false,"canonicalSlug":"synapse-keywords-api-5c222598"}