Understanding multiple documents with a single prompt may use more consumption units than sending the prompt a single document.

See the [AI Hub pricing page](https://docs.instabase.com/policies/pricing-policy) for more information.

Before starting this tutorial, open a chat with two or more documents added to it. Other tutorials in this series can show you how to set that up.

In this example, we're starting in the **Aircraft specs** chat created during an earlier tutorial in this series. That chat has two documents.

When we submit a prompt, chat scans all documents that are *in scope* and builds a reply out of the information it finds in only those documents.

In other words, setting the scope limits the range of documents that chat can use when answering a prompt.

Scope could include a single document, or all of the documents in the left-hand file list, or anything in between.

The document titles shown below the **Query your files** box are the documents that are in scope.

We want to compare the specifications of A330 and A350 airplanes, using information from both documents in the chat's file list

Imagine that only [[A330_specs.pdf]] is currently in scope

To add [[A350_specs.pdf]] to the scope, first click the **Edit message scope** or **(+)** icon

Click the **Edit message scope** or **(+)** icon

Select or deselect documents to add or remove them from scope

In this example, we'll select [[A350_specs.pdf]]

Now we can send a prompt that will look at both documents

Click the **Query your files** field.

Type [[Which airplane seats the most people?]] and hit [[enter]]

A shortcut for removing a document from scope is to click the **X** next to the document's chip below the **Query your files** field

A shortcut for adding a document to scope is to click the **Add file to scope** or **(+)** icon next to the title in the left-hand file list

Instabase

Learn how to understand a collection of documents by sending chat prompts that return answers based on information in all the documents.

Understand multiple documents