詳しい: detailed information and knowledge of a subject
Compare detailed procedural information with a brother who knows the city's old buildings well. Read 詳しい for a quality of content and a person's subject knowledge, preserving the request and the stated topic.
Detailed information to consult in a guide
詳しい (くわしい) can describe detailed information or content. 「手続きの詳しい内容は、案内書を確認してください。」 means “Please consult the guide for detailed information about the procedure.” 詳しい modifies the procedural content.
確認してください is a request to consult the guide. The sentence points to where the detailed content can be checked; it does not say that the reader has already read it or completed the procedure. Read the detail in the content together with the request.
A brother knowledgeable about old buildings
「兄はこの町の古い建物に詳しい。」 means “My older brother knows a great deal about this city's old buildings.” The brother is the subject, and この町の古い建物に gives the topic he knows well. This describes a person's knowledge rather than modifying information.
In 古い建物に詳しい, the knowledge concerns those buildings. 詳しい does not make him knowledgeable in every field. Preserve the topic of this city's old buildings without adding a profession, a qualification, or knowledge of every fact about every building.
Is the content detailed, or does a person know the subject?
In 詳しい内容, the adjective describes the content's quality. In 古い建物に詳しい, it states what a person knows well. Identify the content being modified, the brother as the subject, and the topic linked by に to distinguish the uses.
Consulting the guide is requested, while the brother's knowledge is presented as a current quality. Do not turn the request into a completed action or expand knowledge of particular buildings to every city and field.
What does 「詳しい」 describe in the procedure information and in the brother's knowledge of the city's old buildings?
Show the answer and why
It describes the level of detail in the procedural information and the brother's knowledge of a particular topic, respectively. Consulting the guide remains a request. Knowledge of this city's old buildings does not establish knowledge of buildings in every city or a professional qualification.