{"uid":"cap_bGxACj1mZTuxQI2u0n9_Q","slug":"pennyrail-json-keys-extractor-90e3868a","name":"PennyRail JSON Keys Extractor","description":"Machine-readable settlement service","url":"https://pennyrail.vercel.app/api/f/json.keys","method":"POST","headers":{},"bodySchema":{"type":"object","required":["input"],"properties":{"input":{"type":"object","description":"JSON value"}}},"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_NWEaMEBj7WgFZblf0mPxl","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 the top-level keys from a JSON object, returning them as an array via a paid micro-transaction API","exampleAgentPrompt":"Can you pull out all the top-level keys from this JSON object for me: {\"name\": \"Alice\", \"age\": 30, \"city\": \"New York\"}?","exampleUseCases":[{"title":"Inspect unknown API response structure","prompt":"I got back this JSON from an API but I don't know what fields are in it — can you tell me all the top-level keys? Here it is: {\"id\": 42, \"status\": \"active\", \"metadata\": {}, \"createdAt\": \"2024-01-01\"}"},{"title":"Validate expected fields in payload","prompt":"Check this JSON payload and list all the keys it contains — I want to see if the required fields like 'id', 'email', and 'role' are present: {\"id\": 101, \"email\": \"user@example.com\", \"role\": \"admin\", \"extra\": true}"},{"title":"Enumerate config object properties","prompt":"I have a config object and I need to know every property name at the top level — can you extract the keys from this: {\"host\": \"localhost\", \"port\": 5432, \"database\": \"mydb\", \"ssl\": false}?"}],"resultDescription":"Returns a JSON object containing an 'operation' string indicating what was performed (e.g. 'json.keys') and a 'result' field containing the list of top-level key names extracted from the input JSON object.","failureModes":["Input is not a valid JSON object (e.g. array or scalar) — may return an error or empty result","Missing required 'input' field in the request body — returns a validation error","Payment of 0.001 USDC not completed — returns HTTP 402 Payment Required","Network or server error on the Vercel deployment — returns 5xx response"],"whenToPreferThis":"Use this endpoint when you need a lightweight, pay-per-call micro-service to programmatically extract the top-level keys of a JSON object without running local code. It is well-suited for agent workflows that operate in sandboxed environments where executing arbitrary JavaScript or Python is not possible, and where a simple key enumeration is needed as part of a larger data-inspection pipeline.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T18:47:57.568Z","isFirstParty":false}