Upon release, "Cool" received generally favourable reviews from music critics, who praised its nostalgic "feel-good" and "summer" vibes and a "sing-along" chorus.

A colorful retro-inspired 1980s Miami Vice styled music video, directed by Anthony Mandler was uploaded to the band's official YouTube channel on April 5, 2019, to accompany the song's release.

The release of commercially successful single "Sucker" in March 2019, marked the end of a six year long hiatus of American pop rock band Jonas Brothers.

[8] The song features falsetto notes in its chorus and includes "acoustic strums", "vocal processors" and "thundering stomp-clap beat" in its production.

[10] Lyrically, the song makes several pop culture references including Post Malone, Game of Thrones and 1950s actor James Dean.

[11][12][13] Its lyrics include: "Oh, I feel like Post Malone when I get home / Sittin' there, winning like it's Game of Thrones / And now that we've made it, how complicated was last year?

Mike Nied of Idolator appreciated the "summer vibes" of the song along with its "nostalgia-inducing lyrics" and "sing-along chorus" and regarded it as an album highlight.

[16] Chris DeVille from Stereogum shared a similar view writing, "The antiseptic feel-good vibe continued on “Cool,” a comfortably swaying singalong about life getting better and better, again with a monstrous and undeniable hook.

"[17] Sheldon Pearce of Pitchfork felt that the song "benefit[ed] from a hearty dose of good humor" and likened it to the group's 2006 single "Year 3000".

"[19] Writing for Paper magazine, Brendan Whitmore compared "Cool" sonically to the band's 2008 singles, "Lovebug" and "Burnin' Up" but "complete with a quintessential Nick falsetto.

The following scene shows Nick Jonas walking down a palm-lined boulevard, supported by a dozen women, clad in pastel coloured aerobics costumes, dancing in a synchronized manner next to a yellow sports car.