[1] Scholars have observed that Cassatt's choice to employ vivid colors, loose brushstrokes, and novel perspective to portray the scene makes it a quintessentially Impressionist painting.

[3] The art historian Griselda Pollock, however, has emphasized the constraints that this identity imposed on Cassatt's choice of subject matter, observing that "for bourgeois women, going into town mingling with crowds of mixed social composition was not only frightening because it became increasingly unfamiliar, but because it was morally dangerous.

[4] The scene shown in The Cup of Tea is a depiction of Mary Cassatt's sister Lydia partaking in a daily ritual exclusive to upper-class Parisian women.

[3] In their book on the paintings in the Metropolitan Museum of Art, John K. Howat and Natalie Spassky explain how The Cup of Tea exemplifies Cassatt's “commitment to Impressionism.”[1] The depiction of the subject as well as the deliberate brushwork and coloring align with the Impressionist "idiom".

[1] Frederick Sweet further explains how the eloquent brushstrokes dissolve the line between subject and background and encourage the viewer to see the painting as an "overall conception", not as a portrait.

At the same time, these gloves are made up of “measured” brushstrokes of the recurring pink and white colors to maintain the sense of fluency throughout the piece, consistent with the Impressionist movement.

[6] Weinberg calls further attention to the artist's selective use of detail: “Cassatt’s emphasis on unexceptional details and events of daily life reflect her concern for anecdote rather than elaborate narrative.”[6] Gustave Geffroy, a French art critic, praised Mary Cassatt's The Cup of Tea in an 1881 issue of the journal La Justice: “We prefer above all the woman in the pink dress and bonnet who holds a cup of tea in her gloved hands.” Geffroy goes on to write that Lydia is “exquisitely Parisian,” having been depicted with various nuances in color, texture, and lighting.

Geffroy concludes by explaining how these artistic details come together to create “a delicious work.”[7] Charles-Albert d’Arnoux—otherwise known as Bertall, a French illustrator—takes a more critical stance toward The Cup of Tea in Paris-Journal in April 1881.

[7] In a short comment in L’art moderne, Joris-Karl Huysmans admires the "smiling woman dressed in pink" who sits in her large chair and holds a "little teacup in her gloved hands."

He claims that the gloved hands and little teacup along with the use of pinks and bright colors add “the fine odor of Parisian elegance to the overall tender and peaceful air.”[7] Upon seeing The Cup of Tea at the Impressionist Exhibition of 1881, artist Paul Gauguin wrote: "Miss Cassatt has as much charm, but she has more power.