Frequent paid appearances on RT make you an agent by definition. She also is a favoured guest on the rabid putlerphile Tucker Carlson’s show.
Her FB page on July 16 said :
“Sadomasochism is the only way to describe the Biden Administration’s willingness to impoverish and destroy America in order to destroy and inflict maximum pain on Russia.”
She has been putting out a blizzard of kremlin lies and disinformation for years, but stepped it up in January 2022.
There is an active FB page promoting her as a presidential candidate for 2024.
The following Yahoo/Fox item from March 2022 demonstrates her true loyalties:

Gabbard is a dangerous, evil person; putler’s dream president. More dangerous than the gremlin-like Carlson because she is young, superficially attractive, looks good in a bikini, is ex-military and appeals to the Trump wing of the GOP, despite being a Democrat.
Only morons vote for something like that, Sir Scradge. Yes, we have lots of morons, but not enough to make this creature our president.
I certainly hope you are right Frank.
Unfortunately they said the same about Trump!
Biden says he will run. Obviously his loyalists won’t challenge him, but she will. Nightmare scenario: Trump v Gabbard!
I’m no fan of Trump, even though he did certain things that I approved of, but there is a world of difference between him and Gabbard. Believe me, she has next to no chance to be POTUS!
“There is an active FB page promoting her as a presidential candidate for 2024.”
The famous ice cube in hell has a better chance.