{"slug":"base-token-check-fly-dev-v1-transfer-check-9312e9","title":"Check a Base ERC-20 for a honeypot-style transfer cost before a swap or send","host":"base-token-check.fly.dev","method":"GET","resource":"https://base-token-check.fly.dev/v1/transfer-check","category":"market","description":"Check a Base ERC-20 for a honeypot-style transfer cost before a swap or send. Input: one token address. Output: allow, warn, or block. Block: not a contract or not an ERC-20. Warn: bytecode contains taxFee, liquidityFee, sellFee, buyFee, transferFee, isBlacklisted, or maxTxAmount. USDC warns because","price_listed":0.01,"price_asked":null,"state":"effects","state_label":"Not tested: has real-world effects","checks_7d":0,"answered_7d":0,"latency_ms_median":null,"reported_calls_30d":3,"reported_payers_30d":2,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","queryParams":{"address":"0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913"},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET","HEAD","DELETE"],"type":"string"},"queryParams":{"properties":{"address":{"description":"ERC-20 contract address on Base to check for a transfer fee, blacklist, or max transfer size.","pattern":"^0x[0-9a-fA-F]{40}$","type":"string"}},"required":["address"],"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[],"description_full":"Check a Base ERC-20 for a honeypot-style transfer cost before a swap or send. Input: one token address. Output: allow, warn, or block. Block: not a contract or not an ERC-20. Warn: bytecode contains taxFee, liquidityFee, sellFee, buyFee, transferFee, isBlacklisted, or maxTxAmount. USDC warns because it contains isBlacklisted(address). A selector does not prove the fee, blacklist, or cap runs on every transfer, and this check does not simulate one.","last_updated":"2026-10-10T17:41:56.923Z","schemes":["exact"]}