diff --git a/test-tmux-detector.sh b/test-tmux-detector.sh
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+++ b/test-tmux-detector.sh
@@ -0,0 +1,223 @@
+#!/bin/bash
+# Phase 7 Tmux Detector Acceptance Test — auto-discovery with @tb- prefix
+# Tests the harness-agnostic tmux detector that watches opted-in panes
+set -e
+
+TB_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
+DAEMON_URL="http://127.0.0.1:4000"
+DATA_DIR="$HOME/.local/share/trailboss-tmux-test"
+TEST_BASE="tb-tmux-$$"
+
+# Isolated tmux socket — never touches the user's main server
+TMUX_TEST_SOCK="/tmp/tmux-trailboss-tmux-test-$$"
+TMUX="tmux -S $TMUX_TEST_SOCK"
+
+# Quiet threshold from tmux-detector.ts
+QUIET_THRESHOLD_MS=30000  # 30 seconds default
+POLL_INTERVAL_MS=2000     # 2 seconds
+
+# Cleanup function
+cleanup() {
+  local exit_code=$?
+  echo "[cleanup] tearing down test environment..."
+  $TMUX kill-server 2>/dev/null || true
+  pkill -f "bun.*daemon/index.ts" 2>/dev/null || true
+  pkill -f "tmux-detector.ts" 2>/dev/null || true
+  rm -rf "$DATA_DIR" 2>/dev/null || true
+  rm -f "$TMUX_TEST_SOCK" 2>/dev/null || true
+  if [ $exit_code -ne 0 ]; then
+    echo "[cleanup] exited with error code $exit_code"
+  fi
+}
+trap cleanup EXIT
+
+echo "=== Phase 7 Tmux Detector Acceptance Test ==="
+echo "Acceptance Scenario: harness-agnostic auto-discovery detector"
+echo "Testing: pane with @tb- prefix goes quiet -> appears in queue -> input dequeues"
+echo ""
+
+# Clean slate
+cleanup
+sleep 1
+
+# Start daemon
+echo "[setup] Starting daemon..."
+mkdir -p "$DATA_DIR"
+cd "$TB_DIR/daemon"
+bun index.ts > /tmp/trailboss-daemon-test.log 2>&1 &
+DAEMON_PID=$!
+sleep 2
+
+# Verify daemon started
+if ! curl -s --max-time 1 "$DAEMON_URL/status" >/dev/null 2>&1; then
+  echo "[error] daemon failed to start"
+  cat /tmp/trailboss-daemon-test.log
+  exit 1
+fi
+echo "[setup] daemon running (PID $DAEMON_PID)"
+
+# Start a fresh tmux server for testing
+echo "[setup] Starting isolated tmux server..."
+$TMUX start-server
+sleep 1
+
+# Create a test session with a shell that will go quiet
+echo "[setup] Creating test pane..."
+$TMUX new-session -d -s "test-shell" "bash --noprofile --norc"
+sleep 1
+
+# Get the pane ID
+PANE_ID=$($TMUX display -p -t "test-shell" '#{pane_id}')
+echo "[setup] Created pane $PANE_ID"
+
+# IMPORTANT: Set pane title to @tb-test to opt-in to detection
+$TMUX select-pane -t "$PANE_ID" -T "@tb-test"
+sleep 1
+
+# Verify the pane title was set
+PANE_TITLE=$($TMUX display -p -t "$PANE_ID" '#{pane_title}')
+if [ "$PANE_TITLE" != "@tb-test" ]; then
+  echo "[error] Failed to set pane title. Got: '$PANE_TITLE'"
+  exit 1
+fi
+echo "[setup] Pane title verified: '$PANE_TITLE'"
+
+# Start the tmux detector in background
+echo "[setup] Starting tmux detector (auto-discovery mode)..."
+cd "$TB_DIR"
+bun run daemon/tmux-detector.ts > /tmp/trailboss-detector-test.log 2>&1 &
+DETECTOR_PID=$!
+sleep 2
+
+# Verify detector started
+if ! kill -0 $DETECTOR_PID 2>/dev/null; then
+  echo "[error] detector failed to start"
+  cat /tmp/trailboss-detector-test.log
+  exit 1
+fi
+echo "[setup] detector running (PID $DETECTOR_PID)"
+
+# Check that the pane was registered
+echo "[test] Checking that pane was registered..."
+sleep 3
+if ! grep -q "registered pane" /tmp/trailboss-detector-test.log 2>/dev/null; then
+  # Try checking the log more carefully
+  if grep -q "registered" /tmp/trailboss-detector-test.log 2>/dev/null; then
+    echo "[test] Pane was registered (found in detector log)"
+  else
+    echo "[warn] No registration found in detector log, continuing..."
+  fi
+fi
+
+echo "[test] Waiting for detector to detect pane as stuck..."
+echo "[test] (quiet threshold is ${QUIET_THRESHOLD_MS}ms, poll interval is ${POLL_INTERVAL_MS}ms)"
+
+# Wait for the pane to be detected as stuck
+# This can take up to: quiet threshold (30s) + poll interval (2s) + initial setup time
+WAIT_TIME=0
+MAX_WAIT=40
+while [ $WAIT_TIME -lt $MAX_WAIT ]; do
+  RESPONSE=$(curl -s "$DAEMON_URL/queue")
+  COUNT=$(echo "$RESPONSE" | grep -o '"count":[0-9]*' | grep -o '[0-9]*' || echo "0")
+
+  if [ "$COUNT" -gt 0 ]; then
+    echo "[test] Pane detected as stuck after ${WAIT_TIME}s"
+    break
+  fi
+
+  sleep 1
+  WAIT_TIME=$((WAIT_TIME + 1))
+done
+
+if [ $WAIT_TIME -ge $MAX_WAIT ]; then
+  echo "[fail] Pane was not detected as stuck within ${MAX_WAIT}s"
+  echo "[info] Queue response: $(curl -s "$DAEMON_URL/queue")"
+  echo "[info] Detector log:"
+  cat /tmp/trailboss-detector-test.log
+  exit 1
+fi
+
+# Verify the stuck entry has the expected fields
+echo "[test] Verifying queue entry..."
+QUEUE_RESPONSE=$(curl -s "$DAEMON_URL/queue")
+
+# Check that the session ID is the synthetic tmux session ID (starts with "tmux-")
+if ! echo "$QUEUE_RESPONSE" | grep -q '"session_id":"tmux-' 2>/dev/null; then
+  echo "[fail] Queue entry does not have expected session ID (tmux-*)"
+  echo "[debug] Queue: $QUEUE_RESPONSE"
+  exit 1
+fi
+echo "[test] Session ID format is correct (tmux-*)"
+
+# Extract session_id for later verification
+SESSION_ID=$(echo "$QUEUE_RESPONSE" | grep -o '"session_id":"tmux-[^"]*"' | head -1 | cut -d'"' -f4)
+echo "[test] Session ID: $SESSION_ID"
+
+# Check that the reason is "stopped"
+if ! echo "$QUEUE_RESPONSE" | grep -q '"reason":"stopped"'; then
+  echo "[fail] Queue entry does not have reason=stopped"
+  echo "[debug] Queue: $QUEUE_RESPONSE"
+  exit 1
+fi
+echo "[test] Reason is correct: stopped"
+
+# Check that message exists (should be the prompt line)
+if ! echo "$QUEUE_RESPONSE" | grep -q '"message"'; then
+  echo "[fail] Queue entry does not have message field"
+  echo "[debug] Queue: $QUEUE_RESPONSE"
+  exit 1
+fi
+echo "[test] Message field present"
+
+# Now simulate activity by sending keys to the pane
+echo "[test] Simulating activity in pane to trigger unstuck..."
+$TMUX send-keys -t "$PANE_ID" "echo test activity"
+$TMUX send-keys -t "$PANE_ID" Enter
+
+# Wait for the detector to notice and unstuck the session
+echo "[test] Waiting for detector to unstuck session..."
+WAIT_TIME=0
+MAX_WAIT=15
+while [ $WAIT_TIME -lt $MAX_WAIT ]; do
+  RESPONSE=$(curl -s "$DAEMON_URL/queue")
+  COUNT=$(echo "$RESPONSE" | grep -o '"count":[0-9]*' | grep -o '[0-9]*' || echo "0")
+
+  if [ "$COUNT" -eq 0 ]; then
+    echo "[test] Session unstuck after ${WAIT_TIME}s"
+    break
+  fi
+
+  sleep 1
+  WAIT_TIME=$((WAIT_TIME + 1))
+done
+
+if [ $WAIT_TIME -ge $MAX_WAIT ]; then
+  echo "[fail] Session was not unstuck within ${MAX_WAIT}s"
+  echo "[info] Queue response: $(curl -s "$DAEMON_URL/queue")"
+  echo "[info] Detector log:"
+  tail -20 /tmp/trailboss-detector-test.log
+  exit 1
+fi
+
+# Final verification: session should be gone from queue
+echo "[test] Final verification: queue is empty"
+FINAL_RESPONSE=$(curl -s "$DAEMON_URL/queue")
+FINAL_COUNT=$(echo "$FINAL_RESPONSE" | grep -o '"count":[0-9]*' | grep -o '[0-9]*' || echo "0")
+if [ "$FINAL_COUNT" -ne 0 ]; then
+  echo "[fail] Queue should be empty but has $FINAL_COUNT items"
+  echo "[debug] Queue: $FINAL_RESPONSE"
+  exit 1
+fi
+echo "[test] Queue is empty - session successfully dequeued"
+
+echo ""
+echo "=== PASS ==="
+echo "The tmux detector successfully:"
+echo "  - Auto-discovered a pane with @tb- prefix"
+echo "  - Registered the pane for tracking"
+echo "  - Detected it as stuck when quiet at a prompt"
+echo "  - Enqueued it with reason='stopped'"
+echo "  - Unstuck it when activity was detected"
+echo "  - Dequeued it from the queue"
+echo ""
+echo "The harness-agnostic adapter seam is validated."