It explains the details of JLPT N1.
A summary of linguistic competence required
The ability to understand Japanese used in a variety of circumstances.
One is able to read writings with logical complexity and/or abstract writings on a variety of topics, such as newspaper editorials and critiques, and comprehend both their structures and contents.
One is also able to read written materials with profound contents on various topics and follow their narratives as well as understand the intent of the writers comprehensively.
One is able to comprehend orally presented materials such as coherent conversations, news reports, and lectures, spoken at natural speed in a broad variety of settings, and is able to follow their ideas and comprehend their contents comprehensively.
One is also able to understand the details of the presented materials such as the relationships among the people involved, the logical structures, and the essential points.
Source : http://www.jlpt.jp/e/about/levelsummary.html