This study aims to explore the implications of developing writing tasks for the College Scholastic Ability test by analyzing the argument task in the writing section of the GRE (General Record Examination). As a large-scale writing assessment, the GRE argument task has two unique characteristics: 1) it provides a writing prompt guiding analysis and critical evaluation of logical reasonableness, and 2) it provides reading material that has logical problems. The main implication of the GRE argument task is considered to be the development of writing assessments that ask students to critique the logical reasonableness of reading materials that have some limitations or problems. In order to develop writing assessments for the CSAT that provide students meaningful direction in writing study, we need to explore diverse possibilities for writing tasks. Considering the importance of critical evaluation of the logical soundness of texts, the GRE argument task provides meaningful characteristics that we could consider in developing a writing assessment for the CSAT.