What is GPT (OpenAI)?

1 min read Updated

GPT (Generative Pre-trained Transformer) is OpenAI's family of large language models that have become foundational to the AI agent ecosystem through strong reasoning and extensive tool integrations.

WHY IT MATTERS

OpenAI's GPT models sparked the current AI revolution. GPT-3 demonstrated emergent capabilities, ChatGPT brought AI mainstream, and GPT-4 established the frontier for reasoning and multi-modal understanding.

The GPT ecosystem offers broad tool support: function calling, structured outputs, vision, code interpreter, and web browsing. The OpenAI API has become the de facto standard.

GPT-4's reasoning capabilities — particularly in code generation and multi-step planning — make it popular for complex agent architectures. The o1/o3 series add explicit reasoning steps for even stronger performance.

FREQUENTLY ASKED QUESTIONS

What's the difference between GPT-4 and GPT-4o?
GPT-4o is natively multi-modal, processing text, images, and audio. It's faster and cheaper than GPT-4 Turbo while maintaining comparable quality.
Should I use GPT-4 or Claude for my agent?
Both are excellent. Test with your specific use case. GPT-4 has broader tool ecosystem; Claude excels at long-context and instruction following.
What are reasoning models (o1, o3)?
Models that spend more compute at inference time, explicitly 'thinking' before answering. Stronger on math and coding but slower and more expensive.

FURTHER READING

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