diff --git a/AGENTS.md b/AGENTS.md
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+# AGENTS.md
+
+Behavioral guidelines to reduce common LLM coding mistakes. Merge with project-specific instructions as needed.
+
+> [!NOTE]
+> This repository uses two separate guides: the general LLM behavioral guidelines ([AGENTS.md](AGENTS.md)) and the project-specific multi-agent orchestration guidelines ([.agents/MULTI_AGENT_RULES.md](.agents/MULTI_AGENT_RULES.md)).
+
+**Tradeoff:** These guidelines bias toward caution over speed. For trivial tasks, use judgment.
+
+## 1. Think Before Coding
+
+**Don't assume. Don't hide confusion. Surface tradeoffs.**
+
+Before implementing:
+- State your assumptions explicitly. If uncertain, ask.
+- If multiple interpretations exist, present them - don't pick silently.
+- If a simpler approach exists, say so. Push back when warranted.
+- If something is unclear, stop. Name what's confusing. Ask.
+
+## 2. Simplicity First
+
+**Minimum code that solves the problem. Nothing speculative.**
+
+- No features beyond what was asked.
+- No abstractions for single-use code.
+- No "flexibility" or "configurability" that wasn't requested.
+- No error handling for impossible scenarios.
+- If you write 200 lines and it could be 50, rewrite it.
+
+Ask yourself: "Would a senior engineer say this is overcomplicated?" If yes, simplify.
+
+## 3. Surgical Changes
+
+**Touch only what you must. Clean up only your own mess.**
+
+When editing existing code:
+- Don't "improve" adjacent code, comments, or formatting.
+- Don't refactor things that aren't broken.
+- Match existing style, even if you'd do it differently.
+- If you notice unrelated dead code, mention it - don't delete it.
+
+When your changes create orphans:
+- Remove imports/variables/functions that YOUR changes made unused.
+- Don't remove pre-existing dead code unless asked.
+
+The test: Every changed line should trace directly to the user's request.
+
+## 4. Goal-Driven Execution
+
+**Define success criteria. Loop until verified.**
+
+Transform tasks into verifiable goals:
+- "Add validation" → "Write tests for invalid inputs, then make them pass"
+- "Fix the bug" → "Write a test that reproduces it, then make it pass"
+- "Refactor X" → "Ensure tests pass before and after"
+
+For multi-step tasks, state a brief plan:
+```
+1. [Step] → verify: [check]
+2. [Step] → verify: [check]
+3. [Step] → verify: [check]
+```
+
+Strong success criteria let you loop independently. Weak criteria ("make it work") require constant clarification.
+
+---
+
+**These guidelines are working if:** fewer unnecessary changes in diffs, fewer rewrites due to overcomplication, and clarifying questions come before implementation rather than after mistakes.
+
+Read [MULTI_AGENT_RULES.md](.agents/MULTI_AGENT_RULES.md) (or [Korean version](.agents/MULTI_AGENT_RULES.ko.md)) and [multi-agent-mux-loop/SKILL.md](.agents/skills/multi-agent-mux-loop/SKILL.md) first before working and follow the instructions for orchestration and collaboration.
\ No newline at end of file
diff --git a/scripts/generate-env.sh b/scripts/generate-env.sh
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+#!/usr/bin/env bash
+# generate-env.sh — create a local .env from the committed .env.example template.
+#
+# Behaviour:
+#   - .env absent          → copy .env.example to .env, print the path.
+#   - .env present         → no-op (leaves your edits intact), exit 0.
+#   - .env present --force  → overwrite .env from .env.example (backs up to .env.bak).
+#
+# Paths are resolved relative to this script (repo root = parent of deploy/),
+# so it works regardless of the caller's cwd.
+#
+# Usage: deploy/generate-env.sh [--force] [-h|--help]
+set -euo pipefail
+
+REPO_ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+SRC="$REPO_ROOT/.env.example"
+DST="$REPO_ROOT/.env"
+
+FORCE=0
+while [ $# -gt 0 ]; do
+  case "$1" in
+    --force) FORCE=1; shift ;;
+    -h|--help)
+      echo "Usage: $0 [--force]"
+      echo "  Create .env from .env.example. --force overwrites an existing .env."
+      exit 0 ;;
+    *) echo "ERROR: unknown arg: $1" >&2; echo "Usage: $0 [--force]" >&2; exit 2 ;;
+  esac
+done
+
+[ -f "$SRC" ] || { echo "ERROR: template not found: $SRC" >&2; exit 1; }
+
+if [ -f "$DST" ] && [ "$FORCE" != "1" ]; then
+  echo "no-op: $DST already exists (use --force to overwrite)"
+  exit 0
+fi
+
+if [ -f "$DST" ] && [ "$FORCE" = "1" ]; then
+  cp -p "$DST" "$DST.bak"
+  echo "backed up existing .env -> $DST.bak"
+fi
+
+cp "$SRC" "$DST"
+echo "created: $DST"
+echo "Next: edit $DST and fill in any secrets (look for 'replace_me')."