{"uid":"cap_u2guPDnFwvyJzm4XTcZyh","slug":"delx-commerce-json-contract-check-3df842be","name":"Delx Commerce JSON Contract Check","description":"Pay-per-result APIs for agents. No signup. Exact price. Verifiable delivery. USDC on Base + Solana via x402.","url":"https://commerce.delx.ai/api/v1/x402/json-contract-check?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"contract":{"type":"object","description":"Bounded JSON Schema-like contract using type, required, properties, and enum."},"instance":{"description":"JSON value to check."}}},"responseSchema":{"type":"json","example":{"scope":"bounded structural subset: type, required, properties, enum","valid":true,"errors":[],"schema":"delx/json-contract-check/v1","error_count":0}},"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_1Mr6oL18QLCEo2ZfzKA_N","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":"Validates a JSON value against a bounded JSON Schema-like contract (type, required, properties, enum) and returns validation results with errors","exampleAgentPrompt":"Check whether this JSON object is valid against my contract — the contract requires a 'name' string and an 'age' integer, and 'name' must be one of ['Alice','Bob'], and the instance I want to check is {\"name\":\"Alice\",\"age\":30}.","exampleUseCases":[{"title":"Validate LLM structured output","prompt":"I need you to verify that the JSON the model just returned matches my contract — the contract requires 'title' (string), 'priority' (enum: low, medium, high), and 'due_date' (string), and the instance is {\"title\":\"Fix bug\",\"priority\":\"urgent\",\"due_date\":\"2025-06-01\"}."},{"title":"Guard API payload before processing","prompt":"Before I send this payload to my downstream service, check if it satisfies the contract: required fields are 'user_id' and 'amount', both must be present and 'amount' must be a number — the instance is {\"user_id\":\"u123\",\"amount\":\"fifty\"}."},{"title":"Enforce agent tool output schema","prompt":"My agent tool returned {\"lat\":48.8566,\"lon\":\"2.3522\"} — can you validate it against a contract that requires 'lat' and 'lon' to both be numbers?"}],"resultDescription":"Returns a JSON object with a boolean 'valid' field, an 'errors' array listing any violations, an integer 'error_count', and a 'schema' string identifying the validator version (delx/json-contract-check/v1). A valid instance returns valid=true with an empty errors array; an invalid instance returns valid=false with one or more error descriptions.","failureModes":["Malformed contract (not a valid bounded JSON Schema-like object) — likely returns a 400-style error or validation failure","Instance is undefined or missing — may return an error or treat as null","Contract uses unsupported JSON Schema keywords beyond type/required/properties/enum — unsupported keywords silently ignored or rejected","Payment not included or insufficient USDC — HTTP 402 payment required response","Network timeout or service unavailability — HTTP 5xx error"],"whenToPreferThis":"Use this endpoint when you need a lightweight, pay-per-call, no-signup JSON validation step — especially in agent pipelines that need to confirm structured outputs (e.g. LLM-generated JSON) conform to a bounded contract before acting on them. Prefer it over running a full JSON Schema validator locally when you want verifiable, logged validation with crypto payment receipts, or when the agent environment lacks a schema validation library. Best suited for simple contracts using type, required, properties, and enum — not for complex JSON Schema features like $ref, allOf, or format validators.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-01T00:54:02.484Z","isFirstParty":false,"canonicalSlug":"delx-commerce-json-contract-check-3df842be"}