Despite its title, “Robin Williams: Come Inside My Mind” is a straightforward, conventionally assembled documentary biography of an eccentric, decidedly idiosyncratic comedian and actor. At times that’s a limitation, but overall it’s a good thing. Simply watching Williams in action is probably more interesting than any concerted effort to get inside his head or dissect or approximate his method.

And the nearly two-hour “Come Inside My Mind,” directed by Marina Zenovich (“Roman Polanski: Wanted and Desired”) and premiering Monday night on HBO, delivers the archival goods: copious clips from Williams’s stand-up performances, movies, interviews, his 1988 turn in “Waiting for Godot” at Lincoln Center and the seminal “Mork and Mindy,” debuting on television in 1978. There are ups and downs, particularly among the feature films, but we get to see the irrepressible, unpredictable, inventive Williams on top of his game often enough that the documentary flies by.