Szczepanik said he told her to stop and leave her hands where he could see them, then to write what she was searching for.
She wrote "GUN." Szczepanik wrote that he searched the handbag and found a loaded 9mm pistol with four rounds of ammunition in the magazine and one round in the chamber, along with a second magazine with five rounds of ammunition.
He also found directions from Ohio to "Langley, McLean, Virginia."
She apparently travelled from Ohio, where she has family, to the CIA headquarters, according to court documents. Huth has a Virginia driver's license, and public records show she previously lived in the Richmond area.
In court today, the US Attorney's Office says prosecutors argued Huth suffers from mental health issues and is both a danger and a flight risk. She was wearing a wig when she drove up to the CIA, according to prosecutors, and she had a passport and US$100,000 in cash on her.
They said she had also previously fled the country when facing criminal charges that were left unspecified. She does have an outstanding warrant from March of 2016 for domestic violence, issued in Henrico County.
Huth did not contest detention, and a public defender representing her declined to comment on the case. A status conference is set for May 1.