They were mostly FBI informants instead of agents, acting as FBI assets.
FBI informant "Big Dan" was the guy that drove them to the supposed casing of Whitmer's vacation home, acted as one of the leaders of the militia, and he also spent hours and hours planning the kidnapping. For one. (from memory, the FBI even supplied the addresses to case).
FBI credit cards bought a lot of the ammunition and the stuff involved in the plot.
I believe Caserta (not guilty) was referencing him when in his interviews he talked about how the guys training them were FBI assets as referenced in wikipedia "Chappel taught the group tactical skills he had learned in the U.S. Army."
A confidential FBI informant known as "Big Dan," identified in court as Dan Chappel, testified that he drove plotters involved in the scheme to kidnap Michigan Governor Gretchen Whitmer. Chappel also drove with Adam Fox, the group's ringleader, to scout Whitmer's vacation home.
Dan Chappel (born c. 1987), nicknamed "Big Dan", an Army veteran who served in the Iraq War. He has stated that he joined the Wolverine Watchmen in 2020 after finding them on Facebook, wanting to keep up his firearms skills, but contacted law enforcement after seeing the group's radicalization.[109] After becoming an informant, Chappel became the group's "XO", or executive officer, the second-highest rank in the group,[110] and then its highest-ranked officer after Morrison departed the group due to marital problems.[110] Chappel taught the group tactical skills he had learned in the U.S. Army,[110] offered the group use of a credit card (paid for by the FBI) to buy ammunition and supplies,[111] and in summer 2020 spent hours on the phone with Fox planning the kidnapping.[110]