A true short story is commonly called a 'factual short tale'. It tells real stories in a short format, maintaining the truth while employing storytelling techniques to captivate the readers.
A true short story is often referred to as a 'narrative nonfiction short story'. It presents real events and experiences in a concise and engaging way.
Typically, a true short story is known as an 'authentic short narrative'. It focuses on factual accounts, but with the literary elements to make it interesting and accessible.