
Over 2024–2025 ChatGPT and its sibling models shifted from being purely conversational LLMs to offering end-to-end deep research capabilities:

O4-Mini-Deep-Research is OpenAI’s latest agentic reasoning model, combining the lightweight o4-mini backbone with the advanced Deep Research framework. Designed to deliver fast, cost-efficient deep information synthesis, it enables developers and researchers to perform automated web searches, data analysis, and chain-of-thought reasoning within a single API call.