{"uid":"cap_D131-TrRAEwPvut2_JsGA","slug":"base-toolbox-erc-20-allowance-checker-e51a9d07","name":"Base Toolbox – ERC-20 Allowance Checker","description":"Base toolbox: before you sign on Base — Uniswap v3 preflight, leftover allowances, tx explain, transfer check. $0.10 USDC. Also $0.001 price/gas/ENS. GET /v1/constants free. No CoinGecko key.","url":"https://basetoolbox.cartonpliant.workers.dev/v1/allowances","method":"POST","headers":{},"bodySchema":{"properties":{"input":{"type":"object"},"output":{"type":"object"}}},"responseSchema":{"type":"json","example":{"ok":true,"next":"revoke","leftover":1,"spenders":[]}},"example":null,"exampleRequest":null,"tags":["x402"],"displayCostAmount":"0.1","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":"$0.1/call","primary":{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.1","per":"call","confidence":"exact"},"accepted":[{"kind":"static","protocol":"x402","network":"base","amountUsd":"0.1","per":"call","confidence":"exact"}]},"paymentMethods":[{"uid":"pm_HRJTCa0slqlxRTEFWoOQJ","protocol":"x402","methodType":"crypto","chain":"base","mode":"charge","costAmount":"0.1","costPer":"request","priority":0,"asset":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913","unit":"request","depositMicros":null,"planRef":null}],"brandName":null,"brandSlug":null,"brandBaseUrl":null,"brandDocsUrl":null,"whatItDoes":"Returns leftover ERC-20 token allowances on Base for a given wallet, listing spenders and suggested next actions like revoking","exampleAgentPrompt":"Before I sign this Uniswap trade, can you check my wallet 0xABC...123 for any leftover ERC-20 allowances on Base and tell me if I should revoke anything?","exampleUseCases":[{"title":"Pre-trade allowance audit on Base","prompt":"I'm about to do a Uniswap v3 swap on Base — can you check wallet 0xDEAD...BEEF for any open ERC-20 allowances and flag anything I should revoke before I sign?"},{"title":"Routine DeFi wallet security review","prompt":"Can you scan my Base wallet 0x1234...ABCD for stale token approvals and tell me which spender contracts still have leftover allowances I haven't used?"},{"title":"Post-hack allowance sweep","prompt":"I think my wallet 0x9999...FFFF may have been phished — can you pull all current ERC-20 allowances on Base so I know which spenders to revoke immediately?"}],"resultDescription":"Returns a JSON object with an 'ok' boolean, a recommended 'next' action (e.g. 'revoke'), a numeric 'leftover' allowance amount, and an array of 'spenders' with their associated allowance details — giving a clear picture of which contracts have permission to spend tokens from the wallet.","failureModes":["Invalid or malformed wallet address returns an error","Token contract not found on Base returns empty or error response","Network congestion on Base may cause timeout","Missing required input fields returns a 400-level error","Payment of $0.10 USDC not provided results in 402 Payment Required"],"whenToPreferThis":"Use this endpoint when you need a quick, cheap ($0.10 USDC) on-chain lookup of ERC-20 allowances specifically on the Base network — ideal as a preflight check before signing DeFi transactions, auditing wallet exposure, or building revoke-suggestion workflows. Prefer this over building your own RPC calls when you want structured output with actionable recommendations already included.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-09-15T18:34:23.047Z","isFirstParty":false}