Claude does not know your situation in advance. Even the same question gives a tailored answer when you add the background, goal, and constraints. Providing enough context is at the heart of a good prompt.
Why context matters
Claude reasons only within the information it is given. "Write marketing copy" alone leaves it guessing who it is for and what the product is, so you get a generic line. Tell it the audience, product, and tone, and it narrows the answer to match.
What to include
- Background: what you are working on and what you need
- Goal: what you will do with the result
- Audience: who reads it (beginner/expert, internal/customer)
- Constraints: length, tone, what to avoid, format
- Examples: a good comparable, if you have one
Balancing context against overload
More is not always better. Piling on unrelated information can actually blur the point. Include only what genuinely affects the task.
Worth knowing
Even with good context, anything Claude cannot know — undisclosed facts, recent private information — stays guesswork. Provide the key facts yourself and verify the result. If context was thin, just add more after the first reply and ask again.
Reference: general prompting principles are documented in Anthropic's official docs (docs.claude.com).