An obituary file in the New York Times’s archives. (Green Fuse Films)

Fidel Castro’s death on Friday and the monumental obituaries that have followed have brought renewed attention to the craft of summing up a life. If Castro, who led Cuba for five decades, brought the Cold War to the Western Hemisphere and defied generations of American presidents, was an obvious candidate for front-page, above-the-fold treatment, this first stab at defining the record isn’t always so clear-cut. “Obit,” Vanessa Gould’s lively documentary about the New York Times’s obituary section — which unfortunately doesn’t have a wide release date — is a timely look at, as obituarist Margalit Fox puts it in the film, “the precise point at which [a person] becomes history.”

While it might be clear what an obituary for someone like Castro is for, Gould carefully probes how the section chooses its subjects and what their obituaries are intended to do. As one obituarist puts it, “Being a worthy person and a virtuous person is not the same as being a newsworthy person.” While getting into the New York Times’s Vows section might be a mark of social standing for a couple beginning their marriage, making the obituary section is not a token of a life well-lived. The people who merit an obituary may not be nice or socially correct, but their lives made a mark on the world around them.

And once a worthy subject is identified, the reporting begins. “We are not friends, we are not advocates, we are certainly not any form of grief counselor,” Fox explains. The process of writing an obituary involves a lengthy checklist and a confirmation that the person in question has actually died, since the Times has, on occasion, made the mistake of publishing an obituary for someone who was not, in fact, dead.

It can also involve disabusing families of “this Victorian sensibility that obits have to be demure,” as Fox says. Among the coynesses the obituarists, who are reporters rather than social registrars, have to breach is a desire to keep the details of death private. “I have very little patience with people who don’t want to tell me the cause of death,” Bruce Weber says. “I don’t know why people find the idea of illness that causes death embarrassing.” And as much as people may want to see those they loved memorialized in the obituary section, the reporters have to ask them for photos and other details at precisely the moment when they may be most preoccupied with attempting to plan more private remembrances.

But sometimes, it’s the obituary writers who are surprised. When Fox began reporting the obituary for NASA veteran Jack Kinzler, she was skeptical that he had actually helped to save Skylab when the station lost its heat shield after it launched in 1973. On other occasions, an obituary prepared in advance ends up staying in the vault for decades longer than the writers expected. Elinor Smith, known as a teenager as the Flying Flapper of Freeport, merited an advance obituary because the Times thought that, given her aviation stunts, she was likely to die young. She lived until 2010.

It’s not merely through individual lives that the obituary desk defines history. Fox acknowledges that she and her colleagues work in “an inherently retrospective genre,” which is one of the reasons she often gets complaints about the racial mix of the subjects. To those who are hoping for change, Fox says: “Ask me again in one more generation.” That’s a bit of a dodge where Gould might have pushed harder, but it’s a rare lacuna in this otherwise very sharp documentary.

“There is nothing you can do about dying,” Weber notes at one point. “I thought I just might point that out.” And when we do, the writers at places such as the Times and The Washington Post will weigh our lives as we make our way into history — or not.