Can you programmatically accept a smart contract transaction?

Question

When you connect your wallet, buy, sell, swap etc your prompted to accept the smart contract for connection and for gas fees etc.

Is it possible to accept these prompts without user input, in other words without a user clicking on the accept button and the same for gas fees.

Can you automate this process via API?

So say I first wanted to connect my wallet to some website, I'd click connect wallet, then I'd be promoted to accept this by clicking accept.

Then say I wanted to buy some BTC on a Dex like pancakeswap, I'd be promoted to accept the gas fees.

I want to know if I can auto accept these though API or whatever other method?

Answer 1

From a perspective of the app developer: If you have a private key corresponding to the address, you don't need to invoke the wallet popup. Instead, you can just sign the transaction automatically with the private key.

Example using web3js:

web3.eth.accounts.wallet.add(senderPrivateKey);
web3.eth.sendTransaction({
    from: senderAddress,
    // ...
});

---

From a perspective of the app user: You're limited by what the app offers. If they only allow signing the transaction through MetaMask (and no other way), you can only sign the transaction this way.

You could theoretically create macro that automates clicking on the MetaMask wallet UI, enters your password to the wallet, clicks the send button, ... But anytime the wallet software changes their UI or behavior, you'd need to update the macro.