Comment by brunohaid

One thing that works quite well for me for a couple of model generations now is to mention https://en.wikipedia.org/wiki/Simplified_Technical_English, something along the lines of

  **Use controlled technical English.** Prefer an ASD-STE100 style: use short sentences, direct terms, active voice, and one idea per sentence; avoid slang, hype, vague pronouns, and unnecessary jargon.

in your agents.md. The concept of STE100 seems sufficiently ingrained in the models to eliminate 90% of the annoying fluff.