Sly Cooper was praised for its technical achievements—particularly its use of a variation on cel-shading to create a film noir feel while still rendering as a hand-drawn animated film—and criticized for being too short.

An Official U.S. PlayStation Magazine retrospective describes the gameplay as "mix[ing] one-hit-kill arcade action with Splinter Cell sneaking".

[2] To assist in these stealth moves, the environment contains special areas colored with blue sparkles of light, identified in the game as Sly's thief senses.

[3] Each sub-section of a lair contains a number of clue bottles that, when collected, allow Sly to access a safe in the level that contains a page from the Thievius Raccoonus.

These pages grant Sly new moves to aid in movement, stealth, or combat, such as creating a decoy or dropping an explosive hat.

Two years later, the Cooper Gang infiltrates Interpol headquarters in Paris, France to steal a secret police file containing information about the Fiendish Five.

The Fiendish Five comprises Sir Raleigh, a frog pirate in Wales who built a storm machine to sink ships and steal their treasure; Muggshot, an American bulldog gangster in Utah who took over a city to build a gambling empire; Mz.

Sly defeats each member of The Fiendish Five and takes back their pages of the Thievius Raccoonus, then leaves them for Carmelita to arrest.

During their battle, Clockwerk reveals to Sly that he is himself a master thief; bitter and jealous of the Cooper Clan for eclipsing him with their superior talents, and in retaliation, he converted himself into a machine to gain immortality.

After Clockwerk is defeated, Carmelita ends the truce by attempting to arrest Sly, but she agrees to give him a ten-second head start.

Sly, Bentley, and Murray return to their hideout and continue pulling off heists with the fully recovered Thievius Raccoonus.

Sly Cooper and the Thievius Raccoonus was the second game developed by Sucker Punch Productions, following Rocket: Robot on Wheels (1999) for the Nintendo 64.

Brian Flemming of Sucker Punch called the rendering style "toon-shading", comparing the detailed backgrounds with cel-shading foregrounds to that of animated films.

"[3] The game art team "collected hundreds of photos and drawings of areas that looked like the worlds [they] wanted to create" to generate the backgrounds.

The music was inspired by the artwork from the game, with Hakik stating, "stylistic influences came from a combination of instrument choices and musical character defined and inspired by the locales in the game, and similar composer works like Yoko Kanno and her work on Cowboy Bebop, Henry Mancini, and Carl Stalling."

[15] GameSpot noted that "The game has a fantastic sense of style to its design that is reflected in everything from the animation to the unique use of the peaking fad, cel-shaded polygons.

"[23] Many reviews also appreciated the ease of learning the controls and gameplay; IGN stated that "Sly is incredibly responsive, and though his size seems a little large at times due to his long arms and legs and the cane he carries, skillfully jumping and hitting enemies with precision is a quick study.

[41] The character of Sly Cooper has also been come to be considered as a mascot for the PlayStation systems, alongside both Ratchet & Clank and Jak & Daxter.