Answers with sources attached.
Deep Research writes a report on any topic, with numbered sources you can open. Read its plan first, and stop it at any point.

These screenshots come from the demo build, which uses sample data. The app is not released yet, so what you see can change.
What you see
Deep Research is a tab in chat
Start a report right where you chat. There is no separate app to open.
Your message box
Tell it the topic here, the same way you would ask a question.
You say yes to the plan before it starts.
Research shows its plan first, and you can change it. You can stop it while it works. If it cannot match a source to a claim, it says so instead of making a link.
Step by step
Pick Deep Research
Choose the tab and say what you want to learn.
Read the plan
See how the work will be split up. Change it, or say yes as it is.
Read the report
The report has sections. Each claim has a number. Hover over it to see where it came from.
Keep it
Copy the report with its sources, or send it to Docs to keep working on it.
Questions
How do I know a source is real?
Each number links to the page it came from. If a claim has no matching source, it is flagged so you can see the gap.
Is it good for homework or work reports?
It is a starting point. Always read the sources yourself before you rely on them.
Can I use it today?
Not yet. The app is built and in testing, and it has not been released.