Text introductions are critical. You need to provide just enough information to ensure that students will be able to problem-solve or process increasingly challenging texts successfully. Your job is to unlock the text, make it more accessible, and then allow readers to use their "in-the-head" systems of strategic actions to think about and problem-solve their way through the text.
The introduction should be conversational. The way you shape the conversation can help you attend to anything your students need to know how to do in relation to the text. You want to provide scaffolds that will enable readers to access the full meaning, the language, and the print.
Try this: As you plan your brief introductions, think about the reading process, the demands of the text, and the readers' strengths and needs.
Refer to Teaching for Comprehending and Fluency for suggested teaching moves to support comprehending and fluency in text introductions.