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EVM WETH Unwrap Calldata Builder
x402
EVM WETH Unwrap Calldata Builder is a paid API for AI agents from evm-canon-base.onrender.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-09-15).
Encodes calldata for a WETH-style withdraw (unwrap) operation to convert wrapped native token back to native ETH on EVM chains
Price / call$0.01
Success—
StatusUnknown
How this service works
Build unwrapping calldata (WETH-style withdraw)
Output
Returns ABI-encoded hex calldata for a WETH-style withdraw(uint256) function call, ready to be included as the data field in an EVM transaction sent to the WETH contract address.
Example use cases
DeFi bot unwrapping WETH after swap
“I just swapped some tokens and ended up with 2.0 WETH, but I need native ETH to pay gas — can you build me the calldata to unwrap all 2.0 WETH back to ETH on Base?”
Smart contract wallet withdrawal flow
“Generate the ABI-encoded withdraw calldata for 0.5 WETH so my multisig can queue a transaction to convert it back to native ETH on Base.”
Automated treasury rebalancing pipeline
“As part of my treasury rebalance, I need to unwrap 10 WETH to native ETH — give me the encoded calldata for the WETH withdraw call so I can batch it with my other transactions.”
Technical details
Endpoint
POSThttps://evm-canon-base.onrender.com/encode/unwrapWhen to prefer
Use this endpoint when you need to programmatically generate WETH unwrap calldata without running a local ABI encoder or ethers.js/viem. Ideal for serverless pipelines, cross-language environments, or agents that need to construct EVM transaction data on demand without a full Web3 library dependency.
Side effects
- Invalid or missing amount parameter returns 400 bad request
- Amount exceeds uint256 max value causes encoding error
- Malformed request body returns validation error
- Service temporarily unavailable on Render cold start returns 503
- Payment not attached or insufficient USDC returns 402
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
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