{"uid":"cap_r1PfuHBrUh55-0qcrzzg6","slug":"vextorium-evm-token-approval-revoke-8b5adb28","name":"Vextorium EVM Token Approval Revoke","description":"Build the transaction that revokes a contract's permission over an ERC-20 token (approve(spender, 0)): target and calldata ready to sign in your wallet. Nothing is sent.","url":"https://api.vextorium.com/v1/revoke-approval?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"token":{"type":"string"},"spender":{"type":"string"}}},"responseSchema":{"type":"json","example":{"for":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","data":"0x095ea7b30000000000000000000000002626664c2603336e57b271c5c0b26f421741e4810000000000000000000000000000000000000000000000000000000000000000","note":"Sign and send this transaction from the wallet that granted the allowance.","value":"0","function":"approve(address,uint256)","arguments":["0x2626664c2603336E57B271c5C0b26F421741e481","0"]}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.003","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":"$0.003/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_CWM7sXRlcowSWU_DEUCYf","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.003","costPer":"request","priority":0,"asset":"EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Generates calldata to revoke (zero-out) an ERC-20 token approval for a specified spender on EVM chains","exampleAgentPrompt":"Generate the transaction calldata to revoke the USDC token approval I previously granted to the Uniswap v3 router at 0x2626664c2603336E57B271c5C0b26F421741e481 — the token contract is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913.","exampleUseCases":[{"title":"Revoking DEX router approval","prompt":"I want to revoke the USDC spending approval I gave to the Uniswap v3 router — the token is 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 and the spender is 0x2626664c2603336E57B271c5C0b26F421741e481. Give me the calldata to sign and send."},{"title":"Cleaning up stale DeFi allowances","prompt":"I need to zero out the allowance for token 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 that I granted to the old Aave v2 pool contract at 0x7d2768dE32b0b80b7a3454c06BdAc94A69DDc7A9 — can you build me the revoke transaction?"},{"title":"Post-exploit emergency approval revoke","prompt":"I think my wallet was compromised — please generate the transaction data to revoke the WETH approval I gave to 0xd9e1cE17f2641f24aE83637ab66a2cca9C378B9F using token contract 0xC02aaA39b223FE8D0A0e5C4F27eAD9083C756Cc2 so I can broadcast it immediately."}],"resultDescription":"Returns a JSON object containing: the token contract address (for), raw hex-encoded calldata (data) for an approve(address,uint256) call with amount set to zero, the ETH value to send (value, typically '0'), the function signature (function), decoded arguments array, and a human-readable note instructing the user to sign and send the transaction from the wallet that originally granted the allowance.","failureModes":["Invalid or malformed token address returns an error","Invalid or malformed spender address returns an error","Unsupported token contract may return null or error data","Network connectivity issues may cause request timeout","Missing required fields (token or spender) will fail schema validation"],"whenToPreferThis":"Use this endpoint when you need to programmatically generate ERC-20 approval revocation calldata for an EVM wallet without connecting directly to a node. It is ideal for AI agents that need to produce ready-to-sign transaction data for revoking allowances across any ERC-20 token and spender pair, especially as part of a DeFi security workflow or post-incident response where speed matters. Pay-per-call via USDC/x402 makes it suitable for agent pipelines without subscription overhead.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-19T12:45:38.851Z","isFirstParty":false,"canonicalSlug":"vextorium-evm-token-approval-revoke-8b5adb28"}