Contract Interactor

The Contract Interactor turns any contract's ABI into a form for every function. Point it at an address to load a verified ABI automatically, or paste one in. Reads run against the RPC for free and need no wallet; writes are simulated first, then sent to your wallet to sign.

What it does

• Fetches the verified ABI for a contract from the explorer, or accepts one you paste.
• Follows proxies to the implementation ABI.
• Generates a typed input form for every read and write function.
• Decodes return values into readable output, and surfaces revert reasons before you sign a write.

Getting the ABI

Enter a contract address. The app queries the explorer:

• Verified contract: its ABI is loaded automatically. If the contract is a proxy, the implementation's ABI is fetched and used at the proxy address, shown with a "Proxy → implementation" badge.
• Unverified contract: you will see "Not verified on Blockscout" and a box to paste an ABI. Both a JSON ABI array and human-readable ABI lines (for example, function transfer(address to, uint256 amount)) are accepted.

A summary shows the contract name (when verified), a verified badge, and an explorer link.

Reads and writes

Functions are split into Read (view/pure) and Write (state-changing) tabs, each an accordion with a search filter. Every function gets one field per argument, labeled with its name and type, validated as you type:

• Addresses are checked for validity; booleans use a switch; integers accept whole numbers (negatives for signed types); bytes accept hex; arrays and tuples accept JSON. Payable functions add a Value (ETH) field.

Reading

Fill in the arguments and click Query. The result is rendered by type (exact integers, addresses as links, arrays and structs as a tree, bytes as copyable hex), with a raw-JSON toggle (integers as strings). Reads go straight to the RPC; nothing is proxied, and no wallet is needed.

Writing

Writes need a connected wallet (the Write tab shows a compact connect prompt when you are disconnected). Click Simulate & Write: the call is simulated first, and if it would revert, the reason is shown inline and nothing is sent. If simulation passes, the transaction goes to your wallet; once signed, its progress and a link are shown.

Step by step

1. Paste a contract address; the verified ABI is fetched (or paste your own).
2. Open the Read or Write tab and find a function.
3. Fill in the arguments.
4. Query a read for free, or Simulate & Write to sign a write.

Fees and gas

Reads are free. Writes cost the gas of the transaction you sign; there is no service fee.

Limits and safety

• Reads go to the RPC; the explorer is used only to fetch the ABI. Nothing is proxied through a backend.
• Writes are always simulated before sending, so most reverts are caught before you spend gas.
• If a contract exposes no functions of a kind, that tab shows an empty state. constructor, fallback, and receive are not listed.
• You are responsible for what a write does. Understand the function and its arguments before signing; the tool executes exactly what you enter.