Claude

Claude is a family of large language models and AI assistants built by the company Anthropic, used through a chat app and through developer tools to hold conversations, write and analyze text, work with code, and carry out multi-step tasks.

Claude is the AI assistant made by Anthropic. Underneath it is a large language model — a system trained on very large amounts of text, which is what lets it follow what you write and answer in fluent, relevant language. What Anthropic says about its own approach is unusually specific and public: a training method called Constitutional AI, in which the model is asked to criticize and revise its own draft answers against a written set of principles, rather than relying only on people rating every response by hand. You can reach Claude through a chat app, or connect to it as a service from your own software.

That written set of principles is worth understanding plainly, because it is easy to picture the wrong thing. It is not a filter bolted onto a finished model, scanning replies and blocking the bad ones. It acts during training: the model produces an answer, checks it against the principles, rewrites it, and the improved version becomes material the model learns from. The aim is a model whose ordinary behavior already leans toward being helpful, honest and careful about harm, without a person having to label every individual case. Anthropic keeps releasing new Claude models, so what any given one can do moves; the method of shaping how it behaves is the steadier thing to know.

None of that makes the output safe to accept unchecked. A training method aimed at honesty reduces bad behavior; it does not give a model any way of knowing when it is wrong. Claude will state an incorrect fact in the same steady tone it uses for a correct one — the failure usually called hallucination — and it can quietly misread what you were actually asking for. Treat it the way you would a fast, well-read assistant whose work you have not verified yet: very good for a first draft, an explanation, a summary or a piece of code, and worth reading with your own eyes before it goes anywhere that matters.