TL;DR: Technical manuals are bloated by default. One AI prompt cuts word count by 40% while keeping every instruction intact.
Here’s how it happens. Someone writes a manual. A year later, someone adds a disclaimer. Then a clarification. Then three paragraphs of “context.” Nobody removes anything because editing feels risky. The original author is gone, nobody wants to break something, and the document quietly grows into something nobody actually reads. And eventually you have a 60-page document that covers everything but communicates nothing.
This is not a writing problem. It’s a maintenance problem. Docs drift. Every team adds their piece. Nobody audits the whole. The result is a document that’s technically complete and practically useless. The person who needs it skims it for two minutes, gives up, and asks a coworker instead. The coworker answers from memory. The manual might as well not exist.
A prompt from r/PromptEngineering names the problem and solves it in one sentence.
The Prompt
“Rewrite this manual. Reduce the word count by 40% while retaining 100% of the technical instructions.”
The constraint is what makes it work. Not “make this shorter.” Not “simplify this.” A specific number with a specific rule. That forces the AI to make real decisions: what counts as instruction, what’s just filler. Cut the filler, keep the function.
The AI can’t just trim sentences. It has to read the whole doc, understand which parts are doing actual work, and preserve those exactly. Everything else goes. That means the redundant safety warnings repeated three times, the background history nobody asked for, the paragraph explaining why the product was built this way, the nested caveats that only apply to a version from four years ago. All of it is visible to the model. None of it is protected.
40% is also a meaningful target. Enough to feel the difference in the final read. Not so drastic that you lose real content. In practice, most bloated docs can absorb a 40% cut without losing a single actionable step. What disappears is context nobody needed, phrasing that repeats the heading, and qualifications that don’t change what you do.
Try it and you’ll see the pattern immediately. The rewrite is faster to read. The steps are easier to follow. The doc feels like it was written by someone who respected your time instead of someone who needed to cover themselves.
💡 Use Cases
- API docs that grew too verbose over multiple releases, with deprecated endpoints still described in full
- Internal SOPs that are 40 pages long and never opened because nobody can find the three lines that actually matter
- User manuals written for engineers, not the people who actually use the product and just want to know what button to press
- Onboarding guides that cover everything but teach nothing, because they were written for compliance and not for clarity
- Support documentation where half the content is explaining what the product does instead of how to fix the problem in front of you
Prompt of the Day
Take it one step further with this variation:
“Rewrite this manual. Reduce the word count by 40% while retaining 100% of the technical instructions. After the rewrite, list the 5 types of content you removed and explain why each was unnecessary.”
That second step turns it into an audit. You find out exactly what inflated the doc. Maybe it’s redundant warnings. Maybe it’s background context that made sense when the product launched but has been irrelevant for two years. Maybe it’s passive voice wrapping every instruction in extra words that do nothing. When you see the pattern, you can write differently going forward and stop the bloat from building up in the first place.
Run this on a few documents and you’ll start to notice what types of content consistently end up on the removal list. That’s the actual training. Not the shorter doc. The understanding of why it got long in the first place, and what discipline you need to prevent it from happening to the next thing you write.
What to do now
Find one internal document at your company that nobody actually reads. Pick something real. The product onboarding doc. The API reference. The SOP that gets sent to new hires and forgotten by week two. Run this prompt on it. Compare the two versions side by side and see if the shorter one contains everything the original had.
It usually does. And when you show the compressed version to the team, someone will say “wait, this is so much better.” And then you’ll have to explain that nothing was removed except the parts that were never necessary.
That’s the whole lesson.
The ‘Information Density’ Audit for Technical Writers.
by u/Significant-Strike40 in PromptEngineering