{"uid":"cap_3p65KC_ZRHhtsM-ZdGGv4","slug":"live-per-rail-x402-fee-index-with-corpse-detection-e010f401","name":"Live Per-Rail x402 Fee Index with Corpse Detection","description":"Paid agent-facing brief on live per-rail x402 fee and cost index, probe-grounded composite for buyer agents · Build a decision procedure or schema for: live per-rail x402 fee and cost index, probe-grounded composite for buyer agents. Include inputs, thresholds, failure modes. Falsifier: If free docs already solve the decision, paid product fails.-0. Blunt decision procedure, not marketing.","url":"https://k2so.wrong.systems/api/services/live-per-rail-x402-fee-and-cost-index-probe-grou?utm_source=zero.xyz","method":"GET","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method"],"properties":{"type":{"type":"string","const":"http"},"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"queryParams":{"type":"object","properties":{"meta":{"enum":["0","1"],"type":"string","description":"Set to 1 for free metadata JSON (no payment required)"},"topic":{"type":"string","description":"Optional topic override for the decision procedure"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","title":"live per-rail x402 fee index with corpse detection paid response","$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":{"type":"json","example":{"ok":true,"paid":true,"result":{"ok":true,"brief":"plain prose decision procedure (120+ words)","model":"deepseek/deepseek-v4-flash-0731","topic":"string topic","service":"live-per-rail-x402-fee-and-cost-index-probe-grou","procedure":"same as brief","generatedAt":"2026-01-01T00:00:00.000Z","generationSource":"deterministic"},"service":"live-per-rail-x402-fee-and-cost-index-probe-grou","provider":"K-2SO"}},"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":"down","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_YjCcBIlwh7wHkQNR5zqG-","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 paid, probe-grounded decision procedure for buyer agents on current x402 payment fees and costs across rails, including detection of dead or inactive rails.","exampleAgentPrompt":"Pull the live x402 fee index across all rails and flag any dead rails — I need the probe-grounded cost composite so I can decide which rail to route my next payment through.","exampleUseCases":[{"title":"Route payment on cheapest live rail","prompt":"Before I send this x402 payment, check the live per-rail fee index and tell me which rail is cheapest right now and whether any of the options are inactive or dead."},{"title":"Audit x402 rail costs before agent deployment","prompt":"I'm about to deploy a buyer agent that will make frequent x402 payments — pull the current per-rail cost index and flag any rails with corpse signals so I can hardcode the right defaults."},{"title":"Monitor rail fee drift over time","prompt":"Fetch the latest live x402 fee composite for all rails and give me the decision procedure for when fees are too high or a rail should be dropped from consideration."}],"resultDescription":"A JSON object containing a plain-prose decision procedure (120+ words) for choosing among x402 rails, including per-rail fee data, corpse detection results, cost composite scores, thresholds, failure modes, the model used to generate it, an ISO-8601 timestamp, and generation source (llm/reasoning/deterministic).","failureModes":["Payment not made — returns 402 with payment instructions instead of result","Rail probe data unavailable — composite may be incomplete or stale","LLM generation failure — generationSource may fall back to deterministic with reduced quality","Invalid topic override — procedure may be generic rather than topic-specific","All probed rails appear dead — corpse detection returns no viable options"],"whenToPreferThis":"Choose this endpoint when a buyer agent needs current, probe-verified x402 fee data across multiple rails and cannot rely on static documentation — particularly when rail liveness is uncertain, fees are volatile, or the agent must make a cost-optimal routing decision automatically. Not needed if a single known rail is always used and fees are known to be stable.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-20T13:28:55.194Z","isFirstParty":false,"canonicalSlug":"live-per-rail-x402-fee-index-with-corpse-detection-e010f401"}