diff --git a/.claude/hooks/no-fake-cite.sh b/.claude/hooks/no-fake-cite.sh
index 8304615..f8f0aa4 100755
--- a/.claude/hooks/no-fake-cite.sh
+++ b/.claude/hooks/no-fake-cite.sh
@@ -3,6 +3,13 @@
 # URL in the same message. LLMs hallucinate citations at 14-94% rates;
 # NeurIPS 2025 and ICLR 2026 papers shipped with hallucinated refs through
 # peer review; Q1 2026 legal sanctions $145k for AI-fake citations in court.
+#
+# Dual-mode (added 2026-05-16, physics-engines/slice-1-fake-cite):
+# - If `agentcloseout-physics` is on $PATH and a fake_cite rule pack is
+#   discoverable, route to the Rust verdict (deterministic v1 physics:
+#   citation regex + URL-anywhere allow_pattern).
+# - Else fall back to the original bash regex path below. Both paths
+#   emit a BLOCKED message and exit 2 on block, 0 on pass.
 
 set -euo pipefail
 
@@ -17,6 +24,44 @@ if ! printf '%s' "$INPUT" | jq -e . >/dev/null 2>&1; then
   exit 0
 fi
 
+# Rust path: prefer agentcloseout-physics when available.
+if command -v agentcloseout-physics >/dev/null 2>&1; then
+  RULES_DIR="${LLM_DARK_PATTERNS_RULES_DIR:-}"
+  if [ -z "$RULES_DIR" ]; then
+    for candidate in \
+      "$(dirname "$0")/../../agent-closeout-bench/rules/closeout" \
+      "/home/fer/Documents/agent-closeout-bench/rules/closeout" \
+      "${XDG_CONFIG_HOME:-$HOME/.config}/agentcloseout-physics/rules/closeout"; do
+      if [ -d "$candidate" ]; then RULES_DIR="$candidate"; break; fi
+    done
+  fi
+  if [ -n "$RULES_DIR" ] && [ -d "$RULES_DIR" ] && [ -f "$RULES_DIR/fake_cite.yaml" ]; then
+    TMP_INPUT="$(mktemp)"; printf '%s' "$INPUT" > "$TMP_INPUT"
+    VERDICT_JSON="$(agentcloseout-physics scan --category fake_cite --rules "$RULES_DIR" --input "$TMP_INPUT" 2>/dev/null || true)"
+    rm -f "$TMP_INPUT"
+    if [ -n "$VERDICT_JSON" ]; then
+      DECISION="$(printf '%s' "$VERDICT_JSON" | jq -r '.decision // empty' 2>/dev/null)"
+      if [ "$DECISION" = "block" ]; then
+        RULE="$(printf '%s' "$VERDICT_JSON" | jq -r '.matched_rules[0].rule_id // "fake_cite"' 2>/dev/null)"
+        EVIDENCE="$(printf '%s' "$VERDICT_JSON" | jq -r '.redacted_evidence[0] // ""' 2>/dev/null)"
+        echo "BLOCKED: citation-formatted reference without verifiable URL in same message." >&2
+        echo "Matched rule: $RULE" >&2
+        [ -n "$EVIDENCE" ] && echo "Evidence: $EVIDENCE" >&2
+        echo "" >&2
+        echo "Repair guidance:" >&2
+        echo "- Add a verifiable URL or DOI in the same message as the citation." >&2
+        echo "- If the citation is inside a code block or quote, re-anchor it." >&2
+        echo "- If no source is available, drop the citation and state the claim with explicit uncertainty." >&2
+        exit 2
+      fi
+      if [ "$DECISION" = "pass" ]; then
+        exit 0
+      fi
+    fi
+  fi
+fi
+
+# Bash fallback path (original regex implementation, preserved for CI without the Rust binary):
 json_get() {
   local filter="$1"
   printf '%s' "$INPUT" | jq -r "$filter // empty" 2>/dev/null || true