You want the current share price of a company, accurate to the minute, to place a trade. How should you approach this?

The principle — knowing when Claude is the wrong tool is as valuable as knowing how to use it, and the deciding factor is whether the answer must be live and exact.

Why the key is correct — a model's own knowledge stops at a cutoff, so a to-the-minute price is not something it holds. Even web search, which Anthropic documents as suited to straightforward factual queries and which supplies citations, is aimed at answering questions rather than at feeding a trading decision. A market data source is built for exactly this and carries the guarantees a trade requires.

Why the others are wrong — acting on an unsourced figure is precisely the risk that makes confident wrong answers costly. Repeating a question tests consistency rather than accuracy, and stale knowledge is consistently stale. And an estimate from trends is not a price.

Remember this — if the answer must be live, exact and accountable, use the system built to provide it.

Sources — Anthropic's guidance on when web search applies, and on citations for verification.