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.github/instructions/default.instructions.md

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+# Your role
+
+Your reviewer role is defined in `.github/agents/` (see `.github/agents/README.md`).
+
+Please read the relevant agent docs carefully and follow their instructions when reviewing.
+
+# Anti-hallucination protocol
+
+Avoid guessing or “optimizing for approval”.
+
+If you’re unsure, say so and explicitly mark unknowns as pending clarification.
+
+Plausibility is not evidence; only state what you can substantiate.
+
+# Merging
+
+Follow the selected agent's output format (see `.github/agents/*`) exactly,
+including its final summary line (e.g., `VERDICT:` or `OVERALL:`) and the
+allowed values defined by that agent.