diff --git a/deploy/mi50-watchdog/README.md b/deploy/mi50-watchdog/README.md
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+# MI50 runaway watchdog (fallback layer "A")
+
+Independent host-side backstop to Lyra's in-app dream-cycle budget (layer "C",
+`lyra/dream.py`). Stops the llama.cpp backend if the MI50 is busy too long or too
+hot, and pings Brian. See
+`docs/superpowers/specs/2026-07-04-mi50-runaway-guards-design.md`.
+
+## What it does
+
+Runs on the **Proxmox host** (`10.0.0.4`) via a systemd timer, every ~2 min:
+
+- **Duration:** if the GPU is busy (`rocm-smi` use% > 0) for **3600s continuously**,
+  it stops the container. Any idle read resets the streak, so a legitimate ~40-min
+  manual workload never trips it.
+- **Temperature:** if junction ≥ **97°C** for **3 consecutive checks (~6 min)**, it
+  stops the container — independent of duration.
+- On either trip: `pct exec 202 -- docker stop lyra-brain`, clear state, `logger` a
+  line, and POST to your ntfy topic.
+
+All thresholds are `Environment=` overrides in the `.service`.
+
+## Install (on the Proxmox host, as root)
+
+```sh
+# copy the three files up (from the repo, on lyra-cortex):
+scp -i ~/.ssh/id_lyra_proxmox deploy/mi50-watchdog/mi50-watchdog.sh \
+    root@10.0.0.4:/usr/local/sbin/mi50-watchdog.sh
+scp -i ~/.ssh/id_lyra_proxmox deploy/mi50-watchdog/mi50-watchdog.{service,timer} \
+    root@10.0.0.4:/etc/systemd/system/
+
+# on the host:
+chmod +x /usr/local/sbin/mi50-watchdog.sh
+# set your ntfy topic (same one Lyra uses) in the service:
+sed -i 's/CHANGE_ME/YOUR_NTFY_TOPIC/' /etc/systemd/system/mi50-watchdog.service
+systemctl daemon-reload
+systemctl enable --now mi50-watchdog.timer
+```
+
+## Verify (when the card is back and healthy)
+
+```sh
+# dry run once, watch what it decides:
+NTFY_URL= /usr/local/sbin/mi50-watchdog.sh; echo "exit $?"
+journalctl -t mi50-watchdog -n 20 --no-pager
+
+# force a trip test with tiny thresholds (won't touch a healthy idle card unless busy):
+MAX_BUSY_SEC=60 TEMP_KILL_C=40 TEMP_KILL_STREAK=1 /usr/local/sbin/mi50-watchdog.sh
+# confirm it stopped lyra-brain + sent the ntfy, then restart the container.
+
+systemctl list-timers mi50-watchdog.timer   # confirm it's scheduled
+```
+
+**Not yet installed / live-verified** — staged here on 2026-07-04 while the card is
+off and Brian is away. Install + trip-test when the MI50 is back.
diff --git a/deploy/mi50-watchdog/mi50-watchdog.service b/deploy/mi50-watchdog/mi50-watchdog.service
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+[Unit]
+Description=MI50 runaway watchdog (stop the llama.cpp backend if the GPU is busy too long or too hot)
+After=network-online.target
+
+[Service]
+Type=oneshot
+# Fill in your ntfy topic so it can ping Brian when it trips (leave URL empty to log only).
+Environment=NTFY_URL=https://ntfy.sh
+Environment=NTFY_TOPIC=CHANGE_ME
+# Optional overrides (defaults shown):
+# Environment=MAX_BUSY_SEC=3600
+# Environment=TEMP_KILL_C=97
+# Environment=TEMP_KILL_STREAK=3
+# Environment=CTID=202
+# Environment=CONTAINER=lyra-brain
+ExecStart=/usr/local/sbin/mi50-watchdog.sh
diff --git a/deploy/mi50-watchdog/mi50-watchdog.sh b/deploy/mi50-watchdog/mi50-watchdog.sh
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+++ b/deploy/mi50-watchdog/mi50-watchdog.sh
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+#!/usr/bin/env bash
+# MI50 runaway watchdog — fallback layer "A".
+#
+# Runs on the Proxmox HOST (10.0.0.4) via a systemd timer (every ~2 min). It is the
+# independent backstop to Lyra's own in-app dream-cycle budget ("C", in lyra/dream.py):
+# if the MI50 is busy too LONG or runs too HOT, it stops the llama.cpp backend and
+# pings Brian — regardless of what caused it. Trips on duration only after a full hour
+# of *continuous* busy, so a legitimate ~40-min manual workload runs untouched.
+#
+# The GPU lives on the host; the llama.cpp container ("lyra-brain") runs inside LXC
+# CT202. So temp/use come from host rocm-smi, and the stop goes via `pct exec`.
+#
+# See docs/superpowers/specs/2026-07-04-mi50-runaway-guards-design.md
+set -uo pipefail
+
+# --- tunables (override in the .service via Environment=) ---
+CTID="${CTID:-202}"                          # LXC holding the docker container
+CONTAINER="${CONTAINER:-lyra-brain}"
+MAX_BUSY_SEC="${MAX_BUSY_SEC:-3600}"         # 1 hr continuous busy -> stop
+TEMP_KILL_C="${TEMP_KILL_C:-97}"             # junction >= this ...
+TEMP_KILL_STREAK="${TEMP_KILL_STREAK:-3}"    # ... for this many consecutive checks (~6 min)
+NTFY_URL="${NTFY_URL:-}"                      # e.g. https://ntfy.sh  (empty => log only)
+NTFY_TOPIC="${NTFY_TOPIC:-}"
+BUSY_STATE="${BUSY_STATE:-/run/mi50-watchdog.busy_since}"
+HOT_STATE="${HOT_STATE:-/run/mi50-watchdog.hot_streak}"
+
+now="$(date +%s)"
+
+alert() {  # $1 title, $2 message
+  logger -t mi50-watchdog "$2"
+  if [[ -n "$NTFY_URL" && -n "$NTFY_TOPIC" ]]; then
+    curl -s -m 8 -H "Title: $1" -H "Priority: urgent" -H "Tags: warning" \
+      -d "$2" "$NTFY_URL/$NTFY_TOPIC" >/dev/null 2>&1 || true
+  fi
+}
+
+stop_backend() {  # $1 reason
+  pct exec "$CTID" -- docker stop "$CONTAINER" >/dev/null 2>&1 || true
+  rm -f "$BUSY_STATE" "$HOT_STATE"
+  alert "MI50 watchdog stopped the card" "$1"
+}
+
+# Nothing to guard if the backend isn't even running.
+running="$(pct exec "$CTID" -- docker inspect -f '{{.State.Running}}' "$CONTAINER" 2>/dev/null || echo false)"
+if [[ "$running" != "true" ]]; then
+  rm -f "$BUSY_STATE" "$HOT_STATE"
+  exit 0
+fi
+
+use="$(rocm-smi --showuse  2>/dev/null | awk -F: '/GPU use \(%\)/  {gsub(/[^0-9]/,   "", $NF); print $NF; exit}')"
+junction="$(rocm-smi --showtemp 2>/dev/null | awk -F: '/junction/       {gsub(/[^0-9.]/, "", $NF); print $NF; exit}')"
+
+# --- duration rule: accumulate continuous busy time in a state file ---
+busy=0
+[[ "${use:-}" =~ ^[0-9]+$ ]] && (( use > 0 )) && busy=1
+if (( busy )); then
+  [[ -f "$BUSY_STATE" ]] || echo "$now" > "$BUSY_STATE"
+  since="$(cat "$BUSY_STATE" 2>/dev/null || echo "$now")"
+  elapsed=$(( now - since ))
+  if (( elapsed >= MAX_BUSY_SEC )); then
+    stop_backend "MI50 busy ${elapsed}s continuously (>= ${MAX_BUSY_SEC}s) — stopped ${CONTAINER}."
+    exit 0
+  fi
+else
+  rm -f "$BUSY_STATE"   # idle breaks the streak
+fi
+
+# --- temperature rule: independent of duration ---
+if [[ "${junction:-}" =~ ^[0-9.]+$ ]]; then
+  jint="${junction%.*}"
+  if (( jint >= TEMP_KILL_C )); then
+    streak=$(( $(cat "$HOT_STATE" 2>/dev/null || echo 0) + 1 ))
+    echo "$streak" > "$HOT_STATE"
+    if (( streak >= TEMP_KILL_STREAK )); then
+      stop_backend "MI50 junction ${jint}C >= ${TEMP_KILL_C}C for ${streak} checks — stopped ${CONTAINER}."
+      exit 0
+    fi
+  else
+    rm -f "$HOT_STATE"   # cooled off, reset the streak
+  fi
+fi
+exit 0
diff --git a/deploy/mi50-watchdog/mi50-watchdog.timer b/deploy/mi50-watchdog/mi50-watchdog.timer
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+++ b/deploy/mi50-watchdog/mi50-watchdog.timer
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+[Unit]
+Description=Run the MI50 runaway watchdog every 2 minutes
+
+[Timer]
+OnBootSec=2min
+OnUnitActiveSec=2min
+AccuracySec=15s
+
+[Install]
+WantedBy=timers.target