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Chain of Thought

Prompting technique where the AI model "thinks aloud" — reasoning step by step, improving accuracy on complex questions.

What is Chain of Thought?

Chain of Thought (CoT) is a technique where the AI model solves a problem step by step, explicitly presenting its reasoning. Instead of giving an immediate final answer, the model breaks the task into stages, verifies intermediate results, and builds a logical chain of conclusions.

Why does CoT improve results?

Language models are auto-regressive — they generate text token by token. When a model "writes out" its reasoning, each next token has more context. New models (o3, Claude with extended thinking) have built-in CoT that drastically improves quality on complex problems.

Applications in AI agents

In multi-agent systems, CoT is crucial: a planning agent must "think through" strategy before delegating tasks. Visible reasoning also enables auditability — you can verify why the agent made a specific decision.