Acaster's first book, Classic Scrapes (2017), was developed from a recurring segment on Widdicombe's XFM radio show in which he shared anecdotes of personal mishaps.

[5] His family attended a nondenominational Christian church whose Sunday sermons included humorous anecdotes, sketches recreating Bible stories, and rock music.

[12] A car crash at the age of 18 led him to fixate on the idea of death, so Acaster created a bucket list: items included skydiving and stand-up comedy.

Most of the Welsh leg of the tour was cancelled following a car accident with Acaster at the wheel, which served as the inspiration for The Pictish Trail's single "Dead Connection" (2016).

[24][25] It received four stars out of five from the British Comedy Guide; Matt Wood praised the "more abstract and ambitious routines" but was more critical of the structure, audience participation and slice of life material.

[23] Beth Kahn, in Broadway Baby, gave it three stars, praising the responses to hecklers and physical comedy but critiquing his listless manner and mundane topics.

[27] Giving it three stars, Veronica Lee of The Arts Desk praised the show as well-structured and whimsical, with frequent use of callback, but said that some tropes "feel simply mechanical".

[30] With fictionalised biographic material, he commented on Yoko Ono's impact on The Beatles, Percy Pig sweets, mariachi music and the placeholder names Joe Bloggs and John Doe.

[36] Acaster assumes a fictional background for each routine, themed around the law: his character works as an undercover cop, serves on a jury, leads a honey-based scam and is put into witness protection.

[38] Topics for routines include the 2010 Copiapó mining accident, a teabag analogy for Brexit, the existential question of what preceded the Big Bang and the British Empire.

[46] Hugh Montgomery of The Independent rated Recognise four stars, summarising it as "an acquired taste" of "surreal set-pieces" and "observations as astute as they are trivial" with intelligent callbacks.

[47] Another four-star review—by Bruce Dessau in Evening Standard—found Represent to be Acaster's "most conceptually ambitious set yet", with "copious scope for laughs" and "absolute precision" to delivery, including pauses.

Chortle's Steve Bennett praised Recap as continuing Acaster's "uniquely offbeat" material, "precision of focus", nested twists within routines and gradually unfolding narrative.

[40] In Acaster's next stand-up routine, Cold Lasagne Hate Myself 1999, he discusses his poor experience recording an episode of The Great British Bake Off and the termination of relationships with ex-girlfriends, an agent and a therapist.

[77] Bethy Squires of Vulture reviewed his 2020 appearance on The Big Fat Quiz of the Year as "a great add to the madness", with his unpredictable actions including smearing ice-cream on protective COVID-19 dividers.

[81] Den of Geek reviewers listed Acaster's highlights on the programme: his recurring refusal to greet Horne; the 30-second musical composition "Over My Shoulder" under the name Clump Stump; a live recreation of Grand Theft Auto; and practicing hula-hooping for months.

[89][88]: 43:20–52:10  He discussed his 2019 appearance on The Great British Bake Off in his routine Cold Lasagne Hate Myself 1999, and the mental health issues that he was experiencing at the time.

[97] The Guardian's Brian Logan said that the writing and "heightened reality" reflected Acaster's comedic style, but was less successful in the medium, while Mark Gibbings-Jones called it "delightfully off-kilter".

[104] Alongside Ed Gamble, Lloyd Langford and John Robins, Acaster created The Island (2022), while stuck in New York City due to a snowstorm.

[108] In a three-star review for The Guardian, Stuart Heritage critiqued that the hosts should have been more active participants than "wisecracking observers" led by the engineer Zoe Laughlin.

[132] Edward Wickham of Church Times analysed that it exploits podcast tropes to play "sophisticated games of subversion and irony", but also has "a charmingly traditional, pantomimic feel to the sitcom, reminiscent of radio comedy from the post-war era".

[141] Jamie Atkins of Record Collector gave the book five stars, saying that Acaster "writes about music beautifully and economically" and "skilfully intersperses" album history with his mental state in 2017.

[141] Steve Bennett of Chortle rated the book three stars, calling the personal story "honest, unaffected, poignant – and, yes, entertaining", but commenting that the number of albums mentioned and their obscurity are overwhelming.

[144] Two Christmas specials were recorded, one with Jeff Rosenstock, whose album Worry featured the track which gave Acaster's project its name: "Perfect Sound Whatever".

[150][152] Temps' debut 10-track album, Party Gator Purgatory, was released by Bella Union on 19 May 2023 and explores genres including alt-rock, electronica, hip-hop and jazz.

[160] For Far Out, Tyler Golsen rated Party Gator Purgatory two out of five stars, summarising it as "a random soup that never congeals" due to its lack of direction, large number of contributing artists and combination of genres.

Shuttleworth reviewed it as a "technicolour, maximalist, hugely inventive album" with a "sprightly, playful character" overall, but a number of "unexpectedly moving" commentaries on mental health.

[5] His half-hour programme James Acaster's Findings (on the same channel) was given a 2013 pilot on the topic "Bread", followed by a series in 2014: "Wood", "Fruit", "Wheels" and "Paint".

[53] A Channel 4 executive named Acaster as a comedian whose work falls between alternative comedy and traditional stand-up, due to his subversion of audience expectations and joke structures.

In Repertoire, he recognised the connections to his life and reveals them in the routines as a twist:[9] one episode, Represent, is about loss of religious belief, told through a narrative arc of jury service.