Henri Cramer's '3 Fugitive Thoughts' Op.10 are likely light and agile piano pieces that explore quick passagework and perhaps playful melodic ideas. They would serve as excellent studies in finger dexterity and rapid articulation.
Practice rapid, even scales and arpeggios with a light touch and clear articulation.
3 Pensées fugitives (Op.10) is rated Henle level 5 of 9 — late intermediate repertoire, roughly ABRSM grades 6–7. In the RCM system it corresponds to about level 5.
You should be comfortable at Henle level 5 — meaning you can already play level 4–5 pieces cleanly. Learning it one level early is possible as a stretch piece, but more than that usually leads to months of frustration.
3 Pensées fugitives (Op.10) is available as free public-domain sheet music on IMSLP — the score is linked directly from this page.