How to write custom templates that stop LLMs from hallucinating brand voice

When we first added generative text features to our marketing app the AI output sounded like a generic corporate brochure regardless of the input we supplied. Our early testers noted that the copy lacked any personality causing the generated blogs to look identical to every other tool on the market.

The solution involved moving from broad instructions and building strict structural boundaries into the prompt template. We added three constraints, a mandatory sentence length limit and a rule that requires a specific industry example, in every single output paragraph.

By forcing the model to follow a content framework the quality of the generated drafts improved instantly and consistently. The users stopped spending twenty minutes rewriting the AI text. Began publishing it directly to their blogs.

What formatting rules do you add to your prompts to keep text sounding human?