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Prompting & context engineering

Evidence and uncertainty rules

Also called: ask, don't invent, say when you're unsure

DEFINITION

Instructing the model to ground claims in provided sources, to flag what it's unsure about, and to ask or abstain rather than fabricate when it lacks the facts.

WHY IT MATTERS

This is the prompt-level defence against hallucination. 'Only use the document I gave you, and tell me what's missing' converts a confident guesser into a more honest assistant.

COMMONLY CONFUSED WITH

A guarantee. The rule reduces invention but doesn't eliminate it; high-stakes claims still need a human to check the source.