{"uid":"cap_lBNsFYn6xyxNNgWJDaOJ0","slug":"ethereum-erc-20-allowance-checker-691e8427","name":"Ethereum ERC-20 Allowance Checker","description":"Call when an agent needs ERC-20 allowance(owner, spender) on Ethereum, raw and human when decimals() is readable. Send token, owner, and spender. Read-only. No spend. Send JSON {\"token\":\"0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48\",\"owner\":\"0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045\",\"spender\":\"0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48\"}. Exact $0.002 USDC on Base. Try unpaid POST /v1/sandbox/eth-erc20-allowance first.","url":"https://agentshelf.syntexa.ch/v1/eth-erc20-allowance?utm_source=zero.xyz","method":"POST","headers":{},"bodySchema":{"type":"object","properties":{"owner":{"type":"string","examples":["0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"],"description":"Token holder who granted the allowance. Example: 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045. EIP-55 or all one case."},"token":{"type":"string","examples":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48"],"description":"ERC-20 contract on Ethereum mainnet. Example: 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48 (Circle USDC). allowance(owner, spender) is read-only."},"spender":{"type":"string","examples":["0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48"],"description":"Account allowed to spend the tokens. Example: 0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48. EIP-55 or all one case."}}},"responseSchema":null,"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_zW0U3esLNlA5OVQK3Uyjm","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":"Returns the ERC-20 token allowance (raw and human-readable) that an owner has granted to a spender on Ethereum mainnet","exampleAgentPrompt":"What's the current USDC allowance that 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 has granted to the Uniswap v3 router 0xE592427A0AEce92De3Edee1F18E0157C05861564 on Ethereum mainnet?","exampleUseCases":[{"title":"Pre-flight DeFi approval check","prompt":"Before I submit this swap, check how much USDC (0xA0b86991c6218b36c1d19D4a2e9Eb0cE3606eB48) my wallet 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 has approved the Uniswap router 0xE592427A0AEce92De3Edee1F18E0157C05861564 to spend on Ethereum."},{"title":"Security audit of token approvals","prompt":"I need to audit token approvals — can you look up how much DAI (0x6B175474E89094C44Da98b954EedeAC495271d0F) the address 0xAbCd1234000000000000000000000000000000ab has allowed the Aave lending pool 0x7d2768dE32b0b80b7a3454c06BdAc94A69DDc7A9 to spend on Ethereum mainnet?"},{"title":"Monitor staking contract allowance","prompt":"Check what the current WETH allowance is for owner 0x1234567890abcdef1234567890abcdef12345678 toward the staking contract 0xae7ab96520DE3A18E5e111B5EaAb095312D7fE84 on Ethereum — give me both the raw number and the human-readable amount."}],"resultDescription":"Returns the allowance amount in two forms: raw (as the integer value from the contract) and human-readable (scaled by the token's decimals() value if readable), representing how many tokens the spender is authorized to transfer on behalf of the owner.","failureModes":["Invalid or non-checksummed Ethereum address returns a 400 error","Token contract address does not implement ERC-20 allowance() function returns an error","Ethereum node unavailable or rate-limited returns a 503 or timeout","Decimals not readable — returns raw value only without human-readable amount","Payment not included or insufficient — returns 402 Payment Required; use sandbox endpoint first"],"whenToPreferThis":"Choose this endpoint when you need a read-only, on-chain ERC-20 allowance lookup for Ethereum mainnet and want both raw and decimal-adjusted values in a single call. It's priced at $0.002 USDC per call and has a free sandbox at /v1/sandbox/eth-erc20-allowance for testing. Prefer it over building your own RPC calls when you need a simple, hosted allowance query without managing Ethereum node infrastructure.","instructions":null,"reviewSummary":null,"reviewSummaryHighlights":null,"reviewSummaryConcerns":null,"reviewSummaryGeneratedAt":null,"activationCount":0,"lastUsedAt":null,"lastSuccessfullyRanAt":null,"lastHealthCheckAt":"2026-10-21T07:20:48.424Z","isFirstParty":false,"canonicalSlug":"ethereum-erc-20-allowance-checker-691e8427"}