How AI Agents Work: LLMs, Claude and ChatGPT in Practice

An AI agent is more than just an LLM. Under the hood, each one has several layers: an orchestrator (LangChain, AutoGen, CrewAI), vector memory (Pinecone, Chroma), tools for real-world actions, and observability. The choice of framework and infrastructure affects an agent's quality as much as the model itself.

AI-processed from Machine Learning Mastery; edited by Hamidun News
How AI Agents Work: LLMs, Claude and ChatGPT in Practice
Source: Machine Learning Mastery. Collage: Hamidun News.
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An AI agent is not just a call to a language model such as ChatGPT or Claude. Behind every autonomous agent sits a multilayered architecture, and the choice of each component determines how reliably and predictably the system handles real-world tasks.

Which language models are used in AI agents?

AI agents use GPT-4o, Claude 3.5 Sonnet, Gemini 1.5, and open alternatives such as Llama 3 and Mistral.

How does the choice of LLM affect an AI agent's performance?

A more powerful model handles multistep tasks better, but it costs more and runs more slowly. The choice of model sets the ceiling on what the agent can do.

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Key Questions Answered

Which language models are used in AI agents?

AI agents use GPT-4o, Claude 3.5 Sonnet, Gemini 1.5, and open alternatives such as Llama 3 and Mistral.

How does the choice of LLM affect an AI agent's performance?

A more powerful model handles multistep tasks better, but it costs more and runs more slowly. The choice of model sets the ceiling on what the agent can do.

ZK
Zhemal Khamidun — CPO at Alpina Digital, product manager of AlpinaGPT. Building AI products since 2019. Hamidun News is a pet project that grew into a production aggregator with 6,000+ readers.
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