If your pet eats something it shouldn't the absolute last thing you want is "manual intervention". Have you ever seen how potters cut lumps of doughy clay? They do it with wire. If you pull you can do the same to your pets intestines.
No. In a Bitcoin transaction the fees are implies by in minus out. There's no way of knowing without a proof the value of a particular output, so if you accidentally spend one far below it's actual value you can end up paying an insane fee. People have lost hundred of Bitcoin due to bugs like this, like off by one errors. A malicious or misbehaving API could misstate the value and cause you to unknowingly lose money in this way if you blindly trust them.
See, that's the misconception most people have. What if an API tells you that you have an unspent output worth 0.01 BTC. and you spend it based on this information. If the API lied you could have just spent a 500 BTC output straight to fees with no recourse. If you just know the transaction hash and vout index you have no idea if the value is correct, many wallets reply on faulty information like this with potentially disastrous consequences.
That is incredibly dangerous behavior. You must be validating your own information before you sign any transactions, preferably with a full node or at a bare minimum SPV proofs. If you believe what information a random API gives you (incorrect or malicious, doesn't matter) you can instantly and irreparably lose all of your money.