{"uid":"cap_VZVnYzBwoQxXllFlv1Nz1","slug":"pennyrail-json-key-picker-f36ff8e1","name":"PennyRail JSON Key Picker","description":"Machine-readable settlement service","url":"https://pennyrail.vercel.app/api/f/json.pick","method":"POST","headers":{},"bodySchema":{"type":"object","required":["input"],"properties":{"input":{"type":"object","description":"{value,keys:string[]}"}}},"responseSchema":{"type":"object","required":["operation","result"],"properties":{"result":{},"operation":{"type":"string"}},"additionalProperties":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_WCRJCW0c8uZcGjhAfK7Uq","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":"Extracts a specified subset of keys from a JSON object, returning only the requested fields","exampleAgentPrompt":"Pick just the 'name', 'email', and 'createdAt' fields from this JSON object: {\"id\":123,\"name\":\"Alice\",\"email\":\"alice@example.com\",\"createdAt\":\"2024-01-01\",\"passwordHash\":\"abc\",\"internalNotes\":\"...\"}","exampleUseCases":[{"title":"Trim API response before storing","prompt":"I got a huge user object back from an API but I only need 'userId', 'displayName', and 'avatarUrl' — can you extract just those three fields from the JSON for me?"},{"title":"Sanitize data before logging","prompt":"Strip this event payload down to only the 'eventType', 'timestamp', and 'sessionId' keys before we log it — I don't want PII in the logs."},{"title":"Prepare partial payload for downstream service","prompt":"From this product record, pull out only 'sku', 'price', and 'stock' — that's all the inventory service needs, leave everything else out."}],"resultDescription":"Returns an object containing an 'operation' string describing what was performed, and a 'result' field containing the new JSON object with only the requested keys present. Additional metadata fields may also be included.","failureModes":["Missing 'input' field in request body returns a validation error","Requesting keys that do not exist in the source object may return empty or partial results","Malformed JSON in the input value may cause a parsing error","Payment failure (402) if USDC balance is insufficient or x402 header is missing"],"whenToPreferThis":"Use this endpoint when you need a lightweight, pay-per-call service to programmatically project a specific set of keys from a JSON object without writing custom transformation logic. It is well-suited for agent pipelines that need to sanitize, slim down, or reshape JSON payloads on the fly with minimal overhead.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T18:44:42.080Z","isFirstParty":false}