Prompt pattern
Approachable
Plain, neighbourly language makes the message easy to enter without making it vague.
Fills the tone part of a prompt.
Write as if explaining the offer to a helpful neighbour. Use contractions, keep most sentences under 20 words, and address the reader as "you". Never use "utilise", "leverage", or "seamless", and say what the thing does before saying why it is good.
Use this tone pattern when it changes the result the agent should produce. It provides one concrete direction without deciding unrelated parts of the website.