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OpenVerbs Chain — Read Contract (eth_call)
x402
OpenVerbs Chain — Read Contract (eth_call) is a paid API for AI agents from chain.openverbs.com, paid per call via x402, $0.006/call, status unknown (last checked 2026-09-30).
Calls any read-only (view/pure) function on a deployed EVM contract and returns the decoded result, across Ethereum, Base, Arbitrum, Optimism, and Polygon.
Price / call$0.006
Success—
StatusUnknown
How this service works
Call a read-only (view/pure) function on any deployed contract via eth_call and get the decoded result. Give the contract address and a human-readable signature (e.g. 'balanceOf(address) view returns (uint256)') plus args; include return types to decode outputs, else raw hex is returned. Reads allowances, oracle prices and vault/DAO state. Read-only, no signing. Ethereum, Base, Arbitrum, Optimism, Polygon.
Output
Returns the decoded output of the contract function call (e.g. a uint256 balance, an address, a bool, a tuple) mapped to the return types specified in the function signature. If return types are omitted from the signature, raw hex is returned. The response reflects the on-chain state at the specified block (defaults to latest).
Example use cases
Check DeFi wallet token balance
“What's the WETH balance of 0xd8dA6BF26964aF9D7eEd9e03E53415D37aA96045 on Base? The WETH contract there is 0x4200000000000000000000000000000000000006 — use 'balanceOf(address) view returns (uint256)'.”
Read Chainlink oracle price
“Get the latest ETH/USD price from the Chainlink aggregator at 0x5f4eC3Df9cbd43714FE2740f5E3616155c5b8419 on Ethereum — call 'latestAnswer() view returns (int256)' so I get the decoded price.”
Check Uniswap pool reserves
“Query the reserves of the Uniswap V2 ETH/USDC pool at 0xB4e16d0168e52d35CaCD2c6185b44281Ec28C9Dc on Ethereum using 'getReserves() view returns (uint112,uint112,uint32)' so I can see both token reserves decoded.”
Technical details
Endpoint
POSThttps://chain.openverbs.com/v1/read-contract?utm_source=zero.xyzWhen to prefer
Use this endpoint when you need to read live, authoritative on-chain state from any EVM smart contract with a known ABI or function signature, without needing to sign a transaction. It is ideal for checking token balances, allowances, oracle prices, DeFi protocol state, and DAO governance data across Ethereum, Base, Arbitrum, Optimism, and Polygon. Prefer it over indexers or subgraphs when you need real-time data at a specific block, or when the contract function isn't indexed elsewhere. It is not suitable for state-changing transactions.
Side effects
- Invalid contract address (not a 40-hex 0x address) — request rejected
- Function signature does not match contract ABI — reverts or returns unexpected hex
- Contract reverts the call (e.g. access control, invalid args) — error response returned
- Unsupported chain specified — enum validation failure
- Return types omitted — raw hex returned instead of decoded values
- Arguments count or type mismatch — call may fail or decode incorrectly
- Querying a non-existent historical block — may return empty or error
- Network congestion causing slow RPC response — latency increase
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| args | array | Function arguments in order (numbers may be passed as strings). |
| block | — | Block number or tag (latest, earliest, pending, safe, finalized). Default latest. |
| chain | string | EVM chain to query. One of: ethereum, base, arbitrum, optimism, polygon. Default "ethereum". |
| address | string | Deployed contract address. |
| function | string | Human-readable function signature, e.g. "balanceOf(address) view returns (uint256)". Include the return types to decode the result. |
Tags
x402
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