{"uid":"cap_uKmPCrcKxI0kp36BlKn3Q","slug":"erc-20-token-allowance-lookup-vextorium-d7800a9a","name":"ERC-20 Token Allowance Lookup (Vextorium)","description":"ERC-20 allowance lookup: how much a spender can move from an owner's balance, flagging unlimited approvals.","url":"https://api.vextorium.com/permiso-token-pago?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","$schema":"https://json-schema.org/draft/2020-12/schema","required":["input"],"properties":{"input":{"type":"object","required":["type","method","bodyType","body"],"properties":{"body":{"required":["token","propietario","gastador"],"properties":{"red":{"enum":["base","ethereum","arbitrum","optimism","polygon"],"type":"string","description":"EVM network (default base)"},"token":{"type":"string","description":"Token contract address"},"gastador":{"type":"string","description":"Spender (contract) address"},"propietario":{"type":"string","description":"Owner wallet address"}}},"type":{"type":"string","const":"http"},"method":{"enum":["POST"],"type":"string"},"bodyType":{"enum":["json","form-data","text"],"type":"string"}},"additionalProperties":false},"output":{"type":"object","required":["type"],"properties":{"type":{"type":"string"},"example":{"type":"object","properties":{"red":{"type":["string","null"]},"nota":{"type":["string","number","boolean","object","array","null"]},"token":{"type":["string","null"]},"permiso":{"type":["number","null"]},"contrato":{"type":["string","null"]},"gastador":{"type":["string","null"]},"ilimitado":{"type":["boolean","null"]},"propietario":{"type":["string","null"]}}}}}}},"responseSchema":{"type":"json","example":{"red":"base","nota":null,"token":"USDC","permiso":0,"contrato":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","gastador":"0x3d4e44Eb1374240CE5F1B871ab261CD16335B76a","ilimitado":false,"propietario":"0xb9f06D2734B7E9D7b21B64C4D8b95bd774b71aCf"}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","displayCostAsset":"USDC","priceDynamic":false,"priceHint":null,"priceStatus":"priced","priceSource":"registry","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":"$0.003/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.003","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_ypvIYvxjsuyH-VR2pvpvZ","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":null,"unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Looks up how much of an ERC-20 token a spender is approved to transfer from an owner's wallet, and flags whether the approval is unlimited.","exampleAgentPrompt":"Check how much USDC (contract 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) the Uniswap v3 router (0xE592427A0AEce92De3Edee1F18E0157C05861564) is allowed to spend from my wallet (0xAbCd1234...5678) on Ethereum, and tell me if it's an unlimited approval.","exampleUseCases":[{"title":"Audit unlimited DeFi approvals","prompt":"Check if the Aave v3 pool contract (0x87870Bca3F3fD6335C3F4ce8392D69350B4fA4E2) has unlimited approval to spend my WETH (0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2) from my wallet 0xDead...Beef on Ethereum."},{"title":"Security review before token revoke","prompt":"Before I revoke approvals, can you tell me exactly how much DAI (0x6B175474E89094C44Da98b954EedeAC495271d0F) the 1inch router (0x1111111254EEB25477B68fb85Ed929f73A960582) is authorized to move from 0xMyWallet on Ethereum?"},{"title":"Monitor spending permission on Base","prompt":"Look up the current allowance that the Base Uniswap v3 swap router has to spend USDC from wallet 0xAbc123... on the Base network, and flag if it's set to unlimited."}],"resultDescription":"Returns the approved allowance amount (as a number), a boolean flag indicating whether the approval is unlimited (max uint256), plus echoed fields for the network, token address, spender address, owner address, and an optional note field for additional context.","failureModes":["Invalid or non-checksummed contract/wallet address returns an error","Token address is not a valid ERC-20 contract on the specified network","Network enum value not recognized (must be base, ethereum, arbitrum, optimism, or polygon)","No allowance set (returns 0) which may be confused with an error","RPC node timeout or network congestion causing a slow or failed read","Missing required fields (token, propietario, gastador) causes validation error"],"whenToPreferThis":"Choose this endpoint when you need a direct on-chain read of the ERC-20 allowance between a specific owner and spender pair — especially when you want automatic detection of unlimited approvals (max uint256). It supports five major EVM networks (Base, Ethereum, Arbitrum, Optimism, Polygon) in a single API, making it ideal for cross-chain wallet security audits, DeFi approval monitoring, or pre-transaction permission checks without needing your own RPC infrastructure.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-02T03:54:18.810Z","isFirstParty":false,"canonicalSlug":"erc-20-token-allowance-lookup-vextorium-d7800a9a"}