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+# Tmux Detector Acceptance Test Analysis (tb-4kfc)
+
+**Test Date:** 2026-07-02
+**Bead:** tb-4kfc
+**Test Script:** `test-tmux-detector.sh`
+**Test Iterations:** 5
+
+## Executive Summary
+
+All 5 test iterations **failed with an identical bug**: the test script extracts the wrong `pane_id` from the queue response. The detector is working correctly and properly detecting the test pane, but the test validation logic has a bug.
+
+**Root Cause:** Line 178 in `test-tmux-detector.sh` uses `head -1` to extract the first `pane_id` from the queue JSON, which may be from a pre-existing queue entry (from other active sessions), not the test pane.
+
+## Test Results Summary
+
+| Run | Status | Exit Code | Duration (s) | Notes |
+|-----|--------|------------|--------------|-------|
+| 1   | FAIL   | 1          | 35           | Bug: pane ID mismatch - queue has %22, test pane is %0 |
+| 2   | FAIL   | 1          | 34           | Bug: pane ID mismatch - queue has %22, test pane is %0 |
+| 3   | FAIL   | 1          | 34           | Bug: pane ID mismatch - queue has %22, test pane is %0 |
+| 4   | FAIL   | 1          | 35           | Bug: pane ID mismatch - queue has %22, test pane is %0 |
+| 5   | FAIL   | 1          | 34           | Bug: pane ID mismatch - queue has %22, test pane is %0 |
+
+### Metrics
+
+- **Pass Rate:** 0/5 (0%)
+- **Fail Rate:** 5/5 (100%)
+- **Average Duration:** 34.4 seconds
+- **Min Duration:** 34 seconds
+- **Max Duration:** 35 seconds
+- **Standard Deviation:** ~0.5 seconds (consistent execution time)
+
+## Detailed Analysis
+
+### Bug Explanation
+
+The test creates an isolated tmux server and a test pane (%0). The detector correctly:
+1. Discovers the pane with `@tb-test` title
+2. Registers it for tracking
+3. Detects it as stuck after ~21 seconds
+4. Adds it to the queue with session_id `tmux-%0-[timestamp]`
+
+However, the queue response contains **multiple entries** from other active sessions:
+
+```json
+{
+  "items": [
+    {"pane_id": "%13", "cwd": "/home/coding/claude-print", ...},
+    {"pane_id": "%22", "cwd": "/home/coding/mta-my-way", ...},
+    {"pane_id": "%0", "session_id": "tmux-%0-1783016074495", ...}
+  ],
+  "count": 3
+}
+```
+
+The buggy line in the test:
+```bash
+QUEUE_PANE_ID=$(echo "$QUEUE_RESPONSE" | grep -o '"pane_id":"[^"]*"' | head -1 | cut -d'"' -f4)
+```
+
+This extracts the **first** `pane_id` (%22 from mta-my-way), not the test pane (%0).
+
+### False Positives / False Negatives
+
+- **False Positives (detector flagged non-stuck sessions):** 0 - The detector correctly identified only the stuck test pane
+- **False Negatives (detector missed stuck sessions):** 0 - The detector successfully detected and queued the test pane
+
+The bug is a **test infrastructure bug**, not a detector bug. The detector is functioning correctly.
+
+## Test Execution Consistency
+
+All 5 iterations showed nearly identical execution times (34-35s), indicating:
+- Stable test infrastructure
+- Deterministic failure mode
+- No flaky behavior or race conditions
+- The "pane ID mismatch" failure occurred consistently
+
+### Timeline per iteration (average):
+1. Setup (daemon + tmux + detector): ~8s
+2. Wait for stuck detection: ~21s
+3. Queue verification failure: immediate
+4. Cleanup: ~5s
+
+## Patterns and Observations
+
+### Consistent Behavior
+
+1. **Detection works:** The detector consistently detected the test pane as stuck after ~21 seconds (within the 30s quiet threshold + 2s poll interval)
+
+2. **Queue entry created:** The test pane was always successfully added to the queue with the correct synthetic session_id format (`tmux-%0-[timestamp]`)
+
+3. **Pre-existing entries:** The queue consistently had 1-2 pre-existing entries from other active sessions (%13 from claude-print, %22 from mta-my-way)
+
+4. **Isolation incomplete:** Despite the test creating an isolated tmux socket, the daemon and detector still see queue entries from the main Trail Boss instance running on the same server
+
+### Test Infrastructure Issues
+
+The test attempts to clear pre-existing queue entries (lines 52-64), but this only clears them at the start. New entries can be added by the main Trail Boss instance while the test is running.
+
+## Recommendations
+
+### Fix the Test Script
+
+Line 178 should be changed to:
+```bash
+# Find the queue entry that matches our SESSION_ID, then extract pane_id
+QUEUE_PANE_ID=$(echo "$QUEUE_RESPONSE" | grep -o "\"session_id\":\"$SESSION_ID\"[^}]*\"pane_id\":\"[^\"]*\"" | grep -o '"pane_id":"[^"]*"' | cut -d'"' -f4)
+```
+
+Or simpler: since we already verified the session_id format, we can directly check that our pane_id exists in the queue:
+```bash
+# Check that our test pane's entry exists in the queue (already done in the wait loop)
+# The verification should just confirm that entry's session_id has the tmux- prefix
+```
+
+### Improve Test Isolation
+
+Consider:
+1. Running the daemon on a different port for testing
+2. Using a separate data directory that won't share queue state
+3. Mocking the queue API to avoid cross-contamination
+
+## Conclusion
+
+The tmux detector is **working correctly**. All 5 test failures are due to a test script bug that extracts the wrong pane_id from the queue response. The detector successfully:
+- Auto-discovered the test pane
+- Tracked it for quiet periods
+- Detected it as stuck
+- Created the correct queue entry
+- Would have unstuck it on activity (not reached due to earlier failure)
+
+The test execution was consistent with minimal variance (34-35s), showing no flaky behavior. Once the test script bug is fixed, we expect all 5 iterations to pass.