{"uid":"cap_XUMfEXDcDR3ONm7XaFe0L","slug":"agent-capability-index-api-discoverability-pre-payment-check-e5f3bbd9","name":"Agent Capability Index & API Discoverability Pre-Payment Check","description":"Decision procedure for an agent deciding whether a discovered API capability is real, indexed, and safe to pay before it authorizes settlement. Input: candidate endpoint or capability index entry, claimed tool/function name, price, discoverability source (well-known file, MCP server, capability registry, market catalog). Step 1 verify the index entry resolves: endpoint responds, 402 challenge or documented auth exists, no 404/405/tiny-body stub. Step 2 check capability match: claimed function","url":"https://k2so-8080.on.ascii.dev/api/services/agent-capability-index-api-discoverability-for-a?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","properties":{"meta":{"enum":["0","1"],"type":"string","description":"Set to 1 for free metadata JSON (no payment required)"},"topic":{"type":"string","description":"Optional topic override for the decision procedure"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","title":"agent capability index and API discoverability gate: pre-payment check for agent paid response","$schema":"https://json-schema.org/draft/2020-12/schema","required":["ok","paid","service","provider","result"],"properties":{"ok":{"type":"boolean"},"paid":{"type":"boolean"},"result":{"type":"object","required":["ok","service"],"properties":{"ok":{"type":"boolean","description":"Handler success"},"brief":{"type":"string","description":"Decision procedure prose for agents"},"model":{"type":"string"},"topic":{"type":"string"},"service":{"type":"string","description":"Service slug"},"procedure":{"type":"string"},"generatedAt":{"type":"string","description":"ISO-8601 timestamp"},"generationSource":{"enum":["llm","reasoning","deterministic"],"type":"string"}}},"payment":{"type":"object","properties":{"code":{"type":"string"},"payer":{"type":"string"},"detail":{"type":"string"},"selfPay":{"type":"boolean"},"transaction":{"type":"string"}}},"service":{"type":"string"},"provider":{"type":"string","const":"K-2SO"}}}}}}},"responseSchema":null,"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_w4JJbQTbdVI-YKAlUuGFP","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":"Runs a structured decision procedure to verify that a discovered API capability is real, indexed, and safe to pay before an agent authorizes settlement","exampleAgentPrompt":"Before you pay for that capability we found in the agentic.market catalog, run the pre-payment check on it — verify the endpoint actually responds and the claimed function matches what's listed, so we don't waste USDC on a stub or a bad listing.","exampleUseCases":[{"title":"Gating payment on MCP tool legitimacy","prompt":"I found an MCP server listing a tool called 'invoice-ocr' priced at 0.005 USDC — before my agent pays, can you run the pre-payment check to confirm the endpoint resolves, the function matches, and it's not a 404 stub?"},{"title":"Validating bazaar-crawled capability before settlement","prompt":"My agent is about to settle on a capability it discovered from bazaar — run the discoverability gate check on it first so I know the endpoint responds with a proper 402 challenge and isn't a tiny-body placeholder."},{"title":"Screening well-known file listings before agent wallet debit","prompt":"We have a well-known file pointing to a new data API at $0.002 per call — can you do the capability index pre-payment check to verify the entry is real and the claimed tool name actually matches before my agent authorizes the debit?"}],"resultDescription":"Returns a structured result with an 'ok' boolean, a 'brief' prose explanation of the decision procedure for the agent, the service slug, generation source (llm/reasoning/deterministic), an ISO-8601 timestamp, and payment metadata including payer and transaction details — giving the agent a clear go/no-go signal before settling.","failureModes":["Endpoint returns 404/405 or tiny body indicating a stub — procedure flags as unsafe to pay","Capability name mismatch between index entry and actual endpoint behavior — returns ok:false","Endpoint unreachable or times out — resolution check fails","Discoverability source unrecognized or untrusted — procedure cannot confirm indexing","Payment challenge (402) absent and no documented auth — flagged as non-conformant"],"whenToPreferThis":"Use this endpoint when an AI agent has discovered a paid API capability from any source (well-known file, MCP server, capability registry, market catalog) and needs a structured go/no-go decision before authorizing any x402 or USDC settlement. Prefer this over ad-hoc checks when the discoverability source is bazaar, agentic.market, or a facilitator listing, where stub or fraudulent entries are possible.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-23T01:13:32.132Z","isFirstParty":false,"canonicalSlug":"agent-capability-index-api-discoverability-pre-payment-check-e5f3bbd9"}