{"slug":"402-com-tr-api-x402-base-swap-validity-d3a8a5","title":"The base-swap 0x trade wrapped in a Cobalt validity transaction","host":"402.com.tr","method":"GET","resource":"https://402.com.tr/api/x402/base-swap-validity","category":"market","description":"The base-swap 0x trade wrapped in a Cobalt validity transaction: Base holds your signed tx dormant until your conditions hold, then includes it — a good-till-block/conditional order, no limit-order contract, nobody holding the trade. We never hold funds or keys; you sign and submit to Base's sequenc","price_listed":0.02,"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":1,"reported_payers_30d":1,"networks":["eip155:8453"],"badge":"unverified","paid_checks_7d":0,"paid_ok_7d":0,"example_input":{"method":"GET","pathParams":{},"queryParams":{"amount":"10","beforeBlock":"40000000","buy":"ETH","flashblockIndex":"0","sell":"USDC","slippage":"100","storageOp":">=","taker":"0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045"},"type":"http"},"output_schema":{"$schema":"https://json-schema.org/draft/2020-12/schema","properties":{"input":{"additionalProperties":false,"properties":{"method":{"enum":["GET"],"type":"string"},"pathParams":{"type":"object"},"queryParams":{"properties":{"amount":{"description":"Amount you sell","type":"string"},"beforeBlock":{"description":"Deadline: before this block (recommended)","type":"string"},"buy":{"description":"Token you buy","type":"string"},"flashblockIndex":{"description":"Flashblock index (optional)","type":"string"},"fromBlock":{"description":"Earliest block (optional)","type":"string"},"minNativeBalanceWei":{"description":"Min taker ETH balance in wei (optional)","type":"string"},"sell":{"description":"Token you sell","type":"string"},"slippage":{"description":"Slippage in bps (optional, default 100)","type":"string"},"storageAddress":{"description":"Advanced: pool/token for a storage condition","type":"string"},"storageMask":{"description":"Advanced: mask (hex, optional)","type":"string"},"storageOp":{"description":"Advanced: operator (< <= = != > >=)","type":"string"},"storageSlot":{"description":"Advanced: storage slot (hex)","type":"string"},"storageValue":{"description":"Advanced: compare value (hex)","type":"string"},"taker":{"description":"Your wallet (signs the swap)","type":"string"}},"required":["sell","buy","amount","taker"],"type":"object"},"type":{"const":"http","type":"string"}},"required":["type","method"],"type":"object"}},"required":["input"],"type":"object"},"history":[],"description_full":"The base-swap 0x trade wrapped in a Cobalt validity transaction: Base holds your signed tx dormant until your conditions hold, then includes it — a good-till-block/conditional order, no limit-order contract, nobody holding the trade. We never hold funds or keys; you sign and submit to Base's sequencer. Conditions: beforeBlock (a deadline), fromBlock, flashblockIndex, minNativeBalanceWei, or a caller-supplied storage predicate for price. At least one required.","last_updated":"2026-10-09T11:06:43.744Z","schemes":["exact"]}