{"uid":"cap_TaHZAK73gjg9qzo_8jRs5","slug":"quartermaster-erc-20-allowance-checker-2b6133d1","name":"Quartermaster ERC-20 Allowance Checker","description":"Check an ERC-20 spending allowance on Base; flags unlimited approvals.","url":"https://quartermaster.surewhynot.app/v1/base/allowance","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"],"type":"string"},"queryParams":{"type":"object","required":["owner","spender"],"properties":{"owner":{"type":"string"},"token":{"type":"string","default":"usdc"},"spender":{"type":"string"}}}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object"}}}}},"responseSchema":null,"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_Rcm7wgnPApCtXUoesMplp","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":"Checks the ERC-20 token spending allowance granted by an owner to a spender on Base, and flags if the approval is unlimited.","exampleAgentPrompt":"Can you check how much USDC spending allowance my wallet 0xAbc123... has granted to the Uniswap router at 0xDef456... on Base, and let me know if it's an unlimited approval?","exampleUseCases":null,"resultDescription":"Returns the current ERC-20 token allowance amount approved by the owner address for the spender address on Base, along with a flag indicating whether the approval is unlimited (max uint256). Includes the token and addresses involved.","failureModes":["Invalid Ethereum address format for owner or spender returns a 400 error","Unknown or unsupported token symbol returns an error","RPC or Base node connectivity issues may cause timeout","Missing required owner or spender query parameters returns a 400 error","Payment not provided or insufficient USDC results in a 402 response"],"whenToPreferThis":"Use this endpoint when you need to check the exact ERC-20 token allowance between two Base addresses, especially to detect risky unlimited approvals. Prefer this over generic block explorers when you need a structured, programmatic JSON response with an explicit unlimited-approval flag ready for agent workflows.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-14T00:41:51.455Z","isFirstParty":false}