The FBI's recruitment of Thiel as a CHS puts him among the bureau's most prominent assets, but he is not alone among right-wing figures who have collaborated with the bureau. Trump himself offered to help the FBI fight organized crime in Atlantic City in the early 1980s. Truth Social, the Trump-owned social-media company, has quietly tipped the FBI off to users who threaten violence, even as it seeks to cash in on their anger. At least two of the rioters who showed up to storm the Capitol on January 6 were also FBI informants, as was Enrique Tarrio, the Proud Boys leader who was sentenced to 22 years in prison for seditious conspiracy and other felonies stemming from the Capitol breach. Tarrio reportedly served as a source for federal and local law enforcement, assisting with the prosecution of more than a dozen people.
A spook is a CIA officer or maybe NSA (or at least some sort of spy if you're using the term more loosely).