ChatGPT Deep Research: How It Finds and Uses Websites

If you have heard about ChatGPT Deep Research and want to know whether it changes anything for your website, here is the short answer. ChatGPT Deep Research is a new agent that searches the web for you, reads many pages, and writes a long report with citations. Your site can be one of those cited sources, but only if the agent can reach your pages, read them easily and trust what they say.

OpenAI announced Deep Research on 2 February 2025, so it is only a few days old. In this guide I explain what it is, how it finds and uses websites, what OpenAI has and hasn’t said, and the practical checks I’d make on a site this week.

What Is ChatGPT Deep Research?

Deep Research is a mode inside ChatGPT that does multi-step research on its own. You give it a question, and instead of answering in a few seconds, it spends several minutes searching, reading and comparing sources. At the end it gives you a long, structured report.

Here is what OpenAI shared at launch:

• Who can use it: ChatGPT Pro users first. Pro costs $200 a month and includes up to 100 Deep Research queries a month. OpenAI says Plus and Team users come next, then Enterprise, but it hasn’t given dates.
• The model: a version of OpenAI’s upcoming o3 reasoning model, tuned for web browsing and data analysis.
• How long it takes: between 5 and 30 minutes per task.
• What it can read: text, images and PDFs on the web. You can also upload your own files, such as PDFs and spreadsheets, to give it context.
• What you get: a written report with citations, plus a sidebar that shows a summary of the steps it took and the sources it used.

To start a task, you pick the Deep Research option in the ChatGPT message box and type your request. OpenAI’s own examples are work-style questions, such as market research, product comparisons and policy reviews. It is not meant for quick facts.

Google already has a similar feature called Deep Research in Gemini Advanced, launched in December 2024. So this is a direction more than one company is taking, not a one-off experiment.

How ChatGPT Deep Research Finds and Uses Websites

OpenAI hasn’t published a technical guide for site owners. But from the launch details and the way the sidebar shows its work, the process looks like this:

1. It plans. It reads your request and breaks it into smaller questions. It may ask you a follow-up question first to narrow the task.
2. It searches. It runs many web searches, not just one. Each search can lead to new searches based on what it learns.
3. It reads pages. It opens pages, PDFs and images and pulls out the facts it needs. OpenAI says it can work through a large amount of content in one task.
4. It changes direction. If a source is weak or a lead goes nowhere, it can backtrack and try another path. This is the “reasoning” part that makes it different from a normal chat answer.
5. It analyses. It was trained to use a Python tool, so it can work with numbers it finds, for example comparing figures across sources.
6. It writes and cites. It puts everything into a report and links to the sources behind each claim.

The important point for you is step 3. A normal search engine sends people to your page. Deep Research sends an agent to read your page on someone’s behalf. The person may only see your site as a citation, and may click it only if they want to check a fact.

Which Crawler Visits Your Site?

OpenAI documents three web agents. GPTBot collects content that may be used to train its models. OAI-SearchBot is used for ChatGPT search. ChatGPT-User visits pages when a ChatGPT user’s request needs it, rather than crawling the web on a schedule.

At launch, OpenAI hasn’t announced a separate user agent for Deep Research. Because it browses while working on a user’s request, I’d expect most of its visits to look like ChatGPT-User or to rely on OpenAI’s search results. Until OpenAI says more, I treat all three as relevant and check my logs for each.

If you block these agents in robots.txt or at your firewall, you are very likely blocking Deep Research too. If you want to understand how those rules work, my robots.txt guide covers the syntax and the common mistakes.

Assume It Reads Plain HTML

Googlebot renders JavaScript (runs the code that builds a page in the browser). I don’t assume AI agents do the same. My working rule is simple: if the key facts are not in the HTML your server sends, an AI agent may never see them.

This matters most for prices, specs, tables and FAQs that load through scripts or only appear after a click. Put the important text in the page source.

ChatGPT Deep Research vs ChatGPT Search

People mix these two up, so here is how I see the difference.

Both depend on the same basics: your page has to be reachable, readable and worth citing. Deep Research just goes deeper and leans more on detail.

What Makes a Page Useful to Deep Research

Nobody outside OpenAI knows exactly how it picks sources. But the job it does tells us a lot. It is trying to build an accurate report, so it needs pages with clear, specific, checkable facts. Here is what I’d focus on.

Specific Facts, Stated Plainly

A research agent is looking for the answer to a sub-question, like “What does this tool cost for 10 users?” Pages that state the answer clearly, in one or two sentences near the right heading, are easy to use. Pages that hide the answer in long marketing text are not.

When I review a page with this in mind, I ask one question: could someone copy one paragraph from here into a report and have it make sense on its own?

Original Information

Deep Research reads many sources on the same topic. If your page repeats what ten other pages say, there is little reason to cite you over them. Original data, first-hand testing, your own pricing, your own process and real expertise give it something it can’t get elsewhere.

This is the same thing Google asks for. Google’s guide on creating helpful, reliable, people-first content asks whether your content adds original information or analysis beyond the sources it draws on. That is a good test for AI research tools as well.

Clear Structure

Good headings help an agent find the right section fast. A logical H2 and H3 outline, short paragraphs, lists for steps and simple tables for comparisons all make a page easier to read, for people and machines. If your headings are messy, my guide to heading tags and SEO shows how to fix them.

Signals of Trust

OpenAI admits Deep Research can struggle to tell authoritative information from rumours. That is exactly why trust signals on your page matter. I’d make sure key pages show:

• who wrote or reviewed the content, and why they know the topic
• when it was published or last updated
• where numbers come from, with links to the original source
• clear company details, such as an about page and contact information

PDFs and Data Files

Because Deep Research reads PDFs, your reports, white papers, price lists and spec sheets can now be sources. Many businesses treat PDFs as an afterthought. I’d check that important PDFs have real text (not scanned images), a clear title and up-to-date figures. Better still, put the key facts on an HTML page as well.

Known Limitations Site Owners Should Know

OpenAI was open about the weak points. According to the launch notes, Deep Research:

• can still make up facts or misread a source, although less often than other ChatGPT models
• may struggle to separate rumours from authoritative information
• doesn’t always show its uncertainty, so it can sound more confident than it should
• can have small formatting errors in reports and citations

For site owners, this has two sides. First, your brand could be described wrongly in a report, based on an old forum post or an outdated page. Second, a clear, accurate, up-to-date page on your own site is the best defence against that. If the right answer is easy to find on your site, the agent has less reason to rely on a weaker source.

In my experience, the pages that cause the most confusion are old ones. An outdated pricing page or a discontinued product page that still ranks can easily be picked up. I’d update or redirect those first.

How to Prepare Your Site for ChatGPT Deep Research

None of this needs a new strategy. It is mostly good technical SEO and clear writing. Here is the order I’d work in:

1. Check your robots.txt. Look for rules that block GPTBot, OAI-SearchBot or ChatGPT-User, including broad Disallow: / rules under User-agent: *. Decide on purpose what you allow. You can block training with GPTBot and still allow the others.
2. Check your firewall and CDN. Security tools and bot protection settings can block AI agents even when robots.txt allows them. I usually see this on sites that turned on a “block AI bots” switch without thinking about search.
3. Look at your server logs. Search for the OpenAI user agents and see which pages they request and what status codes they get. Lots of 403 or 5xx errors mean the agent is being turned away.
4. View the page source of key pages. Make sure the main text, prices, specs and FAQs are in the HTML, not loaded only by JavaScript.
5. Rewrite the top of key pages. Answer the main question in the first few sentences. Add clear headings for the sub-questions people actually ask.
6. Add trust details. Show the author, the update date and the sources for any numbers.
7. Clean up old content. Update, merge or redirect outdated pages that could give a research agent the wrong facts about you.

If you only have an hour, I’d do steps 1 to 3. Access problems are the most common and the easiest to fix, and nothing else matters if the agent can’t get in.

How to Tell If Deep Research Is Using Your Site

There is no report from OpenAI that shows when your site was cited. So you have to piece it together.

• Server logs: visits from ChatGPT-User suggest a person’s ChatGPT request led to your page. You can’t tell from the log alone whether it was Deep Research or a normal chat.
• Referral traffic: when a reader clicks a citation, the visit usually shows as a referral from chatgpt.com in GA4. If you haven’t set GA4 up properly yet, start with my GA4 setup guide.
• Test it yourself: if you have Pro access, run Deep Research on questions your customers ask and check the sidebar for your domain.

I’d expect clicks from Deep Research reports to be small in number. People read the report and click only to check something. But those clicks can come from readers doing serious research, so I’d watch which landing pages they reach.

Using Deep Research for Your Own SEO Work

Deep Research is also a tool you can use, not just something that reads your site. For marketers, I can see it helping with:

• a first pass at competitor research, such as how rivals price and position a service
• pulling together background on a topic before you write about it
• finding questions and subtopics that come up across many sources
• summarising long PDFs, reports or documentation

My rule is to treat the report as a draft, not a finished source. Open the citations and check every number before you use it. Given the limits OpenAI listed, I’d never publish a fact from a Deep Research report that I haven’t checked myself.

I’d also skip it for simple tasks. For a quick keyword idea or a short answer, a normal search or chat is faster. At 100 queries a month, I’d save Deep Research for questions that would take me hours by hand.

What I Wouldn’t Do Yet

Deep Research is days old. Expect a wave of advice about “Deep Research optimisation”. I’d be careful with it.

• Don’t create thin pages written only for AI agents. They add nothing a research tool needs.
• Don’t stuff pages with keywords or repeated questions. An agent reading for facts gains nothing from it.
• Don’t pay for “AI citation” services that promise placement. Nobody can promise how an OpenAI model picks sources.
• Don’t block every AI agent in a panic, then forget about it. Make a clear decision you can explain.

This also fits a wider trend. Last month OpenAI released Operator, an agent that uses websites for people. I wrote about what Operator means for websites, and the lesson is the same: sites that are easy for machines to reach and read will be in a better spot.

Conclusion

ChatGPT Deep Research is a research agent that searches, reads and cites the web for its users. For now it is limited to Pro users, but OpenAI plans to widen access. It rewards the same things good SEO always has: pages that are reachable, readable in plain HTML, clearly structured and full of specific, trustworthy facts.

Your next step is simple. Check your robots.txt, your firewall settings and your server logs for OpenAI’s agents this week. Then pick your five most important pages and make sure the main answer sits in the first few sentences.