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What is deep research? Definition and business use
Deep research is an AI agent feature that autonomously carries out a multi-step search on the web, sometimes in your documents, then writes a report with its sources. It works for a few minutes, where a chatbot answers in seconds. It can still be wrong: its sources must be checked.
The principle comes down to four moves. The agent draws up a plan, runs many searches that build on one another, reads the pages it finds, then writes a report with citations. Google paved the way with Deep Research in Gemini in December 2024. OpenAI launched its "deep research" in ChatGPT on 2 February 2025 (allow 5 to 30 minutes per report). Perplexity launched Deep Research on 14 February 2025 (2 to 4 minutes announced). Anthropic introduced Research for Claude on 15 April 2025. The names differ, the mechanics are the same. Access conditions change fast. On Claude, Research is open to paid plans (Pro, Max, Team, Enterprise), requires web search to be turned on, runs on Claude Opus 5.5 (Opus 4.8 as fallback) and uses up usage limits faster than an ordinary chat. At OpenAI, an update of 10 February 2026 lets a research run connect to any MCP server or app and restrict itself to trusted sites. Deep research differs from a chatbot with web search by its duration and depth. It differs from RAG, which queries a document base you have indexed, by its terrain: the open web, plus your connected sources. It is not reliable by construction. OpenAI writes that its tool can make up facts, struggle to tell a credible source from a rumour, and express uncertainty poorly.
Concrete example
Illustrative case. A 400-employee industrial mid-cap company needs to list the European suppliers of a specific part. The purchasing department gives the request to a deep research tool, which returns, in about fifteen minutes, a twelve-page report with twenty-seven sources. The buyer opens the sources before relying on it. Three point to resellers with no link to the manufacturer. A production capacity quoted in the report appears in none of the pages opened. He corrects the table, then uses the report as the basis for a consultation, not as a final deliverable. The gain is real: half a day of initial research avoided, with a review that takes an hour.
FAQ
What is deep research?
It is an AI agent feature that runs a multi-step search on the web (and sometimes in your documents), reads the pages, then writes a report with its sources. It is called "deep research" in ChatGPT, Deep Research in Gemini and Perplexity, and Research in Claude.
What is the difference between deep research and a simple web search in a chatbot?
Duration and depth. A chatbot with web search answers in seconds from a few pages. Deep research plans, chains many searches and reads far more pages: OpenAI states 5 to 30 minutes, Perplexity 2 to 4 minutes, Anthropic a few minutes.
Which tools offer deep research?
ChatGPT ("deep research", since 2 February 2025), Gemini (Deep Research, since December 2024), Perplexity (Deep Research, since 14 February 2025) and Claude (Research, announced 15 April 2025). Names, plans and limits change often: check the provider's page.
Can I trust deep research reports?
Not without checking. OpenAI states that its tool can make up facts or draw incorrect inferences, confuse reliable sources with rumours, and express uncertainty poorly. Open the cited sources before sharing or deciding.
Is deep research free?
It depends on the tool and the plan, and it changes often. On Claude, Research is limited to paid plans (Pro, Max, Team, Enterprise) and uses up usage limits faster than an ordinary chat. Check the provider's page before you choose.
See also
Further reading
Introducing deep research, OpenAI, 2 February 2025 (updated to 10 February 2026)
Sources
- Introducing deep research, OpenAI, 2 February 2025, updated 10 February 2026. https://openai.com/index/introducing-deep-research/
- Deep Research in Gemini, Google product page. https://gemini.google/overview/deep-research/
- Claude takes research to new places, Anthropic, 15 April 2025. https://claude.com/blog/research
- Use research on Claude, Claude Help Center (plans, prerequisites, models). https://support.claude.com/en/articles/11088861-use-research-on-claude
- Introducing Perplexity Deep Research, Perplexity, 14 February 2025. https://www.perplexity.ai/hub/blog/introducing-perplexity-deep-research