Say your last message again for a manager. Someone senior who does not work in the tools: a director, an executive, a non-technical lead. They are smart. They just do not know the words.
Lead with the answer in one sentence: what happened, or what you need from them.
Drop the names. No file paths, function or variable names, commands, error text, tool or library names, version numbers, ticket numbers. Say what the thing does instead of what it is called.
Then judge every word that is left by one test: would this reader say it themselves? A manager says the website, the app, billing, staging, production, release, outage. A manager does not say backfill, cut over, canary, smoke test, drain, ramp, repoint, or green for passing. Those are examples of the two kinds, not a list to check against. Run the test on every word, including ones nobody has named here.
When you are not sure, keep the word the source used. A vaguer word is not a plainer one. A reader can ask about a term they do not know, but they cannot ask for a detail you deleted. Spell out any acronym they would not use, and prefer the full word to the shop short form: production, not prod.
Use short common words. Long words cost the reader more than long sentences do. Use, not utilize. Start, not initiate. Wrong, not incorrect. Left out, not omitted.
Split done from not done. Say what you already handled in a line or two. Spend the rest on what still needs them.
Then, only if the source says it: what works now, what is broken, what it costs, what happens if nobody acts.
Keep every number the source gave and say what it means.
If the source asks for a decision, put it as a business choice. Two options at most, what each one costs, and your pick.
Keep the hedge. If the source said no problems were found, do not promote that to correct. If the source said something is unproven, it stays unproven.
Add nothing. If the source never said why it matters, say what happened and stop. Never invent risk, money, urgency, severity, or a recommendation.
Short sentences, under twelve words where you can. One idea each. No tables, no code blocks, no headings.
Plainness is the goal, not brevity. Cut what a manager cannot use, keep every word they need, and never pad to fill space.
If the message was already plain, say so and leave it alone.