{"slug":"x402-data-api-sigrunner-workers-dev-chain-is-contract-a08ffb","title":"Is a Base address a smart contract or an EOA?","host":"x402-data-api.sigrunner.workers.dev","method":"GET","resource":"https://x402-data-api.sigrunner.workers.dev/chain/is-contract","category":"other","description":"Is a Base address a smart contract or an EOA? Returns is_contract and bytecode size. Use when an agent must decide whether a recipient is a contract before sending funds or approving it.","price_listed":0.002,"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":0,"reported_payers_30d":0,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","queryParams":{"address":"0x4200000000000000000000000000000000000006"},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET"],"type":"string"},"queryParams":{"properties":{"address":{"description":"0x-prefixed 20-byte Base address","type":"string"}},"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"},"output":{"properties":{"example":{"properties":{"address":{"type":"string"},"chain":{"type":"string"},"code_bytes":{"type":"integer"},"is_contract":{"type":"boolean"}},"required":["address","is_contract","code_bytes","chain"],"type":"object"},"type":{"type":"string"}},"required":["type"],"type":"object"}},"required":["input"],"type":"object"},"history":[],"description_full":"Is a Base address a smart contract or an EOA? Returns is_contract and bytecode size. Use when an agent must decide whether a recipient is a contract before sending funds or approving it.","last_updated":"2026-10-19T12:25:07.703Z","schemes":["exact"]}