If I may ask, why will a Federal Government Agency send ordinary 0.00001 BTC into your wallet address, which is less than a dollar just to watch you? Or how much have you got in your Coinbase Bitcoin wallet address or account in total, are they up to 7 figures? (I.e million dollars), Because that's the only reason that might make FBI try to monitor you in other to investigate and know If the money you have were a product of fraud or either money laundering. Hence, inasmuch as the amount sent is less than a dollar, it likely to be a dusting attack.
Dust attacks can be from any people, not only from government like FBI.
Dust attacks can be done manually or with tools, and if you have fund, want to do dust attack, you can do it, no one can stop you. It's only up to you whether you see dust attack means something for you.
[INFO - DISCUSSION] Bitcoin Dust Limit.