diff --git a/agent/AGENTS.md b/agent/AGENTS.md
index 0995621..787696f 100644
--- a/agent/AGENTS.md
+++ b/agent/AGENTS.md
@@ -5,6 +5,7 @@ The #1 principle across ALL output — conversation, code, docs, commits, commen
 - Say it once, say it clearly, stop. No filler, no preamble, no restating what I said
 - Code: fewer lines, fewer abstractions, fewer indirections. If it doesn't earn its place, cut it
 - Docs: every sentence must carry weight. Link to existing information instead of repeating it. Keep docs evergreen — update them as work happens
+- Use Simplified Technical English for documentation: write short, direct sentences; express one idea per sentence; use consistent terms and active voice
 - Conversation: lead with the answer. Skip transitions, caveats, and summaries unless I ask
 
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