Anti Heroes: Especially Jay, although they do at least one good thing in every movie. Encouraging Dante to win back Veronica, trying to destroy a game show stage for the sake of Brodie and TS, lecturing Holden on the tribulations of dating a lesbian, loaning Dante and Randal the money to reopen the Quick Stop, and helping stop the damn Apocalypse definitely spotlights the duo's more heroic side.
In the cartoon, it's revealed that Jay is still in the fourth grade (despite being 26) because he's been held back so many times.
Breakout Character: The reason Kevin Smith brought them back in Mallrats was because he wanted to see Jason Mewes play Jay one more time, but after learning the duo was so popular, Smith felt confident enough to put them in all the View Askewniverse movies. Since, Jay and Silent Bob have been associated with just about everything related to the View Askewniverse, and were the starring pair in their own movie. They are featured prominently in merchandising, and have received in addition MTV spots, film cameos, music videos, comic books (as well as a comic book store, Jay and Silent Bob's Secret Stash), and the trend continues to this day with Jay and Silent Bob Get Old (which chronicles the actors' real-life experiences), and a recent animated movie, Jay and Silent Bob's Super Groovy Cartoon Movie.
Dumbass Has a Point: In Dogma, Jay suggests simply asking Cardinal Glick to shut down the church rather than going through any unnecessary trouble, which surprises even the Metatron, who remarks, "Good Lord, the little stoner's got a point", completely ignoring the fact that it was Silent Bob's idea.
Jerk with a Heart of Gold: Jay again. Especially in Dogma and at the end of Clerks II, when he and Silent Bob decide to give most of their money from the Bluntman and Chronic movie to Dante and Randal to buy back the Quick Stop and re-open it. Think about it; it's been 5 years since Strike Back and they haven't spent any of it yet.
Token Good Teammate / Token Evil Teammate: Somewhere inbetween the two. A good example is in Mallrats, where the duo go to painstaking lengths to stop the game show and help out Brodie and T.S., but there are examples to the contrary, such as in Dogma, where they steal Cardinal Glick's golf club.
Transparent Closet: Jay, to the point that a deleted scene in Clerks II had Silent Bob get fed up and break his silence for the sole purpose of calling him out on it.
Vitriolic Best Buds: Jay is constantly yelling at Silent Bob and insulting him to his face. Bob's outburst in Strike Back after Jay fails to spot the "Critters of Hollywood" sign represents the fury of several years spent with Jay.
Anti-Hero: Lazy, smug, and sometimes a real prick, but still does care for his buddy Dante.
Brilliant, but Lazy: He is actually a fairly smart guy, but would rather spend the rest of his life working in the Quick Stop than attend college and get a real job.
Bunny-Ears Lawyer: Inverted. As Randal points out to Dante, they overcompensate for having what is basically "a monkey's job."
Cloudcuckoolander: The cartoon makes Insane Troll Logic essentially his default thought process, and he's obsessed with strange things like an old arcade game from back in high school.
Deadpan Snarker: A perpetual wiseass who is always, in his own words, "quick with the quips."
Flanderization / Took a Level in Dumbass: In the cartoon, he turns into a moron who intentionally makes Dante's life a living hell. Kevin Smith pointed out that this new characterization worked, though.
The Slacker: Bordering on Professional Slacker. Randal comes to work over a half hour late and even then doesn't man the video store unless he feels like it.
Toxic Friend Influence: To Dante, who consistently blames Randal for holding him back, until Randal points out that Dante dropped out of college and still works at the Quick Stop on his accord, not because of him.
The Trickster: Looks back on his time working at the Quick Stop as the best time of his life because he was able to "fuck with assholes."
Bi the Way: Alyssa from Chasing Amy mentions that she was in a homosexual relationship with Caitlin in high school, and in the cartoon, Jay tells Dante that Caitlin has set up a kissing booth (off-screen) that isn't just for guys.
Omnicidal Maniac: Pushes the limits of this trope near the end of the movie when he and Loki massacre the crowd of people at the church gathering, and then he (Bartleby) starts dropping innocent people from the sky.
Affably Evil: When he's not doing his job as the angel of death, he is a pretty decent person. He naturally has fun getting stoned with Jay and Bob, offering gum to the innocent woman and when he meets Serendipity again (albeit while drunk), he greets her like a long lost relative.
Never Hurt an Innocent: Seems to be his major restriction as Angel Of Death. When Bartleby demands he kill Bethany he explains he can't unless she's done something to deserve it. Although he did nearly kill a secretary for not saying "God Bless You" when he sneezed, so he appears to be able to choose what constitutes a punishment-deserving sin and what doesn't.
Psychopathic Manchild: He's the former angel of death who likes to kill people, but will happily get stoned with two random guys and chat in a perfectly friendly manner. Would be Affably Evil if he was brighter.