diff --git a/.github/copilot-instructions.md b/.github/copilot-instructions.md
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+# RTK — Token-Optimized CLI
+
+**rtk** is a CLI proxy that filters and compresses command outputs, saving 60-90% tokens.
+
+## Rule
+
+Always prefix shell commands with `rtk`:
+
+```bash
+# Instead of:              Use:
+git status                 rtk git status
+git log -10                rtk git log -10
+cargo test                 rtk cargo test
+docker ps                  rtk docker ps
+kubectl get pods           rtk kubectl pods
+```
+
+## Meta commands (use directly)
+
+```bash
+rtk gain              # Token savings dashboard
+rtk gain --history    # Per-command savings history
+rtk discover          # Find missed rtk opportunities
+rtk proxy <cmd>       # Run raw (no filtering) but track usage
+```
diff --git a/.github/hooks/rtk-rewrite.json b/.github/hooks/rtk-rewrite.json
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+++ b/.github/hooks/rtk-rewrite.json
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+{
+  "hooks": {
+    "PreToolUse": [
+      {
+        "type": "command",
+        "command": "rtk hook copilot",
+        "cwd": ".",
+        "timeout": 5
+      }
+    ]
+  }
+}