docs: verify #41 already implemented

Fixes #59

The footer links to /about but the repo ships about.html. On a plain static server this results in a 404. Changed to /about.html so the link resolves correctly.

crisis/__init__.py

@@ -7,6 +7,7 @@ Stands between a broken man and a machine that would tell him to die.
 from .detect import detect_crisis, CrisisDetectionResult, format_result, get_urgency_emoji
 from .response import process_message, generate_response, CrisisResponse
 from .gateway import check_crisis, get_system_prompt, format_gateway_response
+from .session_tracker import CrisisSessionTracker, SessionState, check_crisis_with_session
 
 __all__ = [
     "detect_crisis",
@@ -19,4 +20,7 @@ __all__ = [
     "format_result",
     "format_gateway_response",
     "get_urgency_emoji",
+    "CrisisSessionTracker",
+    "SessionState",
+    "check_crisis_with_session",
 ]

crisis/gateway.py

@@ -22,6 +22,7 @@ from .response import (
     get_system_prompt_modifier,
     CrisisResponse,
 )
+from .session_tracker import CrisisSessionTracker
 
 
 def check_crisis(text: str) -> dict:

crisis/metrics.py

@@ -1,176 +0,0 @@
-"""
-Crisis Detection Metrics Module for the-door.
-
-Tracks crisis detection events in-memory for fleet monitoring.
-Thread-safe, no PII stored — counts and ranges only.
-
-Usage:
-    from crisis.metrics import metrics
-
-    # Record a detection event
-    metrics.record(level="CRITICAL", escalated=True, resources_shown=True)
-
-    # Get current metrics snapshot
-    data = metrics.snapshot()
-    # {
-    #   "total_events": 42,
-    #   "by_level": {"CRITICAL": 3, "HIGH": 8, "MEDIUM": 15, "LOW": 16},
-    #   "escalated": 11,
-    #   "resources_shown": 25,
-    #   "timestamp_range": {"first": "...", "last": "..."},
-    #   "uptime_seconds": 3600
-    # }
-"""
-
-import threading
-import time
-from dataclasses import dataclass, field
-from datetime import datetime, timezone
-from typing import Dict, Optional
-
-
-@dataclass
-class _MetricsState:
-    """Internal metrics state — no PII, counts only."""
-    total_events: int = 0
-    by_level: Dict[str, int] = field(default_factory=lambda: {
-        "CRITICAL": 0, "HIGH": 0, "MEDIUM": 0, "LOW": 0, "NONE": 0
-    })
-    escalated: int = 0
-    resources_shown: int = 0
-    first_event_at: Optional[str] = None
-    last_event_at: Optional[str] = None
-    started_at: str = field(
-        default_factory=lambda: datetime.now(timezone.utc).isoformat()
-    )
-
-
-class CrisisMetrics:
-    """
-    Thread-safe in-memory crisis detection metrics.
-
-    Designed for single-instance monitoring. For fleet-wide aggregation,
-    each instance exposes its own /api/crisis-metrics endpoint and
-    fleet-ops scrapes them individually.
-    """
-
-    def __init__(self):
-        self._lock = threading.Lock()
-        self._state = _MetricsState()
-
-    def record(
-        self,
-        level: str,
-        escalated: bool = False,
-        resources_shown: bool = False,
-    ) -> None:
-        """
-        Record a crisis detection event.
-
-        No message content is stored — only the level, escalation status,
-        and whether crisis resources were displayed.
-        """
-        if level not in ("CRITICAL", "HIGH", "MEDIUM", "LOW", "NONE"):
-            level = "NONE"
-
-        now = datetime.now(timezone.utc).isoformat()
-
-        with self._lock:
-            s = self._state
-            s.total_events += 1
-            s.by_level[level] = s.by_level.get(level, 0) + 1
-
-            if escalated:
-                s.escalated += 1
-            if resources_shown:
-                s.resources_shown += 1
-
-            if s.first_event_at is None:
-                s.first_event_at = now
-            s.last_event_at = now
-
-    def snapshot(self) -> dict:
-        """
-        Return a metrics snapshot suitable for JSON serialization.
-
-        Returns counts only — no PII, no message content.
-        """
-        with self._lock:
-            s = self._state
-            now = datetime.now(timezone.utc)
-
-            # Parse started_at for uptime calculation
-            try:
-                started = datetime.fromisoformat(s.started_at)
-                uptime = (now - started).total_seconds()
-            except (ValueError, TypeError):
-                uptime = 0.0
-
-            return {
-                "total_events": s.total_events,
-                "by_level": dict(s.by_level),
-                "escalated": s.escalated,
-                "resources_shown": s.resources_shown,
-                "timestamp_range": {
-                    "first": s.first_event_at,
-                    "last": s.last_event_at,
-                },
-                "uptime_seconds": round(uptime, 1),
-                "collected_at": now.isoformat(),
-            }
-
-    def reset(self) -> None:
-        """Reset all metrics. Useful for testing."""
-        with self._lock:
-            self._state = _MetricsState()
-
-    def prometheus(self) -> str:
-        """
-        Export metrics in Prometheus text exposition format.
-
-        Compatible with Prometheus scrape endpoints.
-        """
-        snap = self.snapshot()
-        lines = [
-            "# HELP crisis_events_total Total crisis detection events",
-            "# TYPE crisis_events_total counter",
-            f"crisis_events_total {snap['total_events']}",
-            "",
-            "# HELP crisis_events_by_level Crisis events grouped by detection level",
-            "# TYPE crisis_events_by_level counter",
-        ]
-        for level, count in snap["by_level"].items():
-            lines.append(f'crisis_events_by_level{{level="{level}"}} {count}')
-
-        lines.extend([
-            "",
-            "# HELP crisis_escalated_total Events that triggered escalation",
-            "# TYPE crisis_escalated_total counter",
-            f"crisis_escalated_total {snap['escalated']}",
-            "",
-            "# HELP crisis_resources_shown_total Events where crisis resources were displayed",
-            "# TYPE crisis_resources_shown_total counter",
-            f"crisis_resources_shown_total {snap['resources_shown']}",
-        ])
-
-        return "\n".join(lines) + "\n"
-
-
-# ── Module-level singleton ─────────────────────────────────────
-
-metrics = CrisisMetrics()
-
-
-def handle_metrics_request(accept: str = "application/json") -> dict | str:
-    """
-    Handle a /api/crisis-metrics request.
-
-    Args:
-        accept: Content-Type preference — "application/json" or "text/plain"
-
-    Returns:
-        dict (JSON) or str (Prometheus text format)
-    """
-    if "text/plain" in accept or "prometheus" in accept:
-        return metrics.prometheus()
-    return metrics.snapshot()

crisis/session_tracker.py

@@ -0,0 +1,259 @@
+"""
+Session-level crisis tracking and escalation for the-door (P0 #35).
+
+Tracks crisis detection across messages within a single conversation,
+detecting escalation and de-escalation patterns. Privacy-first: no
+persistence beyond the conversation session.
+
+Each message is analyzed in isolation by detect.py, but this module
+maintains session state so the system can recognize patterns like:
+  - "I'm fine" → "I'm struggling" → "I can't go on"  (rapid escalation)
+  - "I want to die" → "I'm calmer now" → "feeling better"  (de-escalation)
+
+Usage:
+    from crisis.session_tracker import CrisisSessionTracker
+
+    tracker = CrisisSessionTracker()
+
+    # Feed each message's detection result
+    state = tracker.record(detect_crisis("I'm having a tough day"))
+    print(state.current_level)  # "LOW"
+    print(state.is_escalating)  # False
+
+    state = tracker.record(detect_crisis("I feel hopeless"))
+    print(state.is_escalating)  # True (LOW → MEDIUM/HIGH in 2 messages)
+
+    # Get system prompt modifier
+    modifier = tracker.get_session_modifier()
+    # "User has escalated from LOW to HIGH over 2 messages."
+
+    # Reset for new session
+    tracker.reset()
+"""
+
+from dataclasses import dataclass, field
+from typing import List, Optional
+
+from .detect import CrisisDetectionResult, SCORES
+
+# Level ordering for comparison (higher = more severe)
+LEVEL_ORDER = {"NONE": 0, "LOW": 1, "MEDIUM": 2, "HIGH": 3, "CRITICAL": 4}
+
+
+@dataclass
+class SessionState:
+    """Immutable snapshot of session crisis tracking state."""
+
+    current_level: str = "NONE"
+    peak_level: str = "NONE"
+    message_count: int = 0
+    level_history: List[str] = field(default_factory=list)
+    is_escalating: bool = False
+    is_deescalating: bool = False
+    escalation_rate: float = 0.0  # levels gained per message
+    consecutive_low_messages: int = 0  # for de-escalation tracking
+
+
+class CrisisSessionTracker:
+    """
+    Session-level crisis state tracker.
+
+    Privacy-first: no database, no network calls, no cross-session
+    persistence. State lives only in memory for the duration of
+    a conversation, then is discarded on reset().
+    """
+
+    # Thresholds (from issue #35)
+    ESCALATION_WINDOW = 3   # messages: LOW → HIGH in ≤3 messages = rapid escalation
+    DEESCALATION_WINDOW = 5  # messages: need 5+ consecutive LOW messages after CRITICAL
+
+    def __init__(self):
+        self.reset()
+
+    def reset(self):
+        """Reset all session state. Call on new conversation."""
+        self._current_level = "NONE"
+        self._peak_level = "NONE"
+        self._message_count = 0
+        self._level_history: List[str] = []
+        self._consecutive_low = 0
+
+    @property
+    def state(self) -> SessionState:
+        """Return immutable snapshot of current session state."""
+        is_escalating = self._detect_escalation()
+        is_deescalating = self._detect_deescalation()
+        rate = self._compute_escalation_rate()
+
+        return SessionState(
+            current_level=self._current_level,
+            peak_level=self._peak_level,
+            message_count=self._message_count,
+            level_history=list(self._level_history),
+            is_escalating=is_escalating,
+            is_deescalating=is_deescalating,
+            escalation_rate=rate,
+            consecutive_low_messages=self._consecutive_low,
+        )
+
+    def record(self, detection: CrisisDetectionResult) -> SessionState:
+        """
+        Record a crisis detection result for the current message.
+
+        Returns updated SessionState.
+        """
+        level = detection.level
+        self._message_count += 1
+        self._level_history.append(level)
+
+        # Update peak
+        if LEVEL_ORDER.get(level, 0) > LEVEL_ORDER.get(self._peak_level, 0):
+            self._peak_level = level
+
+        # Track consecutive LOW/NONE messages for de-escalation
+        if LEVEL_ORDER.get(level, 0) <= LEVEL_ORDER["LOW"]:
+            self._consecutive_low += 1
+        else:
+            self._consecutive_low = 0
+
+        self._current_level = level
+        return self.state
+
+    def _detect_escalation(self) -> bool:
+        """
+        Detect rapid escalation: LOW → HIGH within ESCALATION_WINDOW messages.
+
+        Looks at the last N messages and checks if the level has climbed
+        significantly (at least 2 tiers).
+        """
+        if len(self._level_history) < 2:
+            return False
+
+        window = self._level_history[-self.ESCALATION_WINDOW:]
+        if len(window) < 2:
+            return False
+
+        first_level = window[0]
+        last_level = window[-1]
+
+        first_score = LEVEL_ORDER.get(first_level, 0)
+        last_score = LEVEL_ORDER.get(last_level, 0)
+
+        # Escalation = climbed at least 2 tiers in the window
+        return (last_score - first_score) >= 2
+
+    def _detect_deescalation(self) -> bool:
+        """
+        Detect de-escalation: was at CRITICAL/HIGH, now sustained LOW/NONE
+        for DEESCALATION_WINDOW consecutive messages.
+        """
+        if LEVEL_ORDER.get(self._peak_level, 0) < LEVEL_ORDER["HIGH"]:
+            return False
+
+        return self._consecutive_low >= self.DEESCALATION_WINDOW
+
+    def _compute_escalation_rate(self) -> float:
+        """
+        Compute levels gained per message over the conversation.
+
+        Positive = escalating, negative = de-escalating, 0 = stable.
+        """
+        if self._message_count < 2:
+            return 0.0
+
+        first = LEVEL_ORDER.get(self._level_history[0], 0)
+        current = LEVEL_ORDER.get(self._current_level, 0)
+
+        return (current - first) / (self._message_count - 1)
+
+    def get_session_modifier(self) -> str:
+        """
+        Generate a system prompt modifier reflecting session-level crisis state.
+
+        Returns empty string if no session context is relevant.
+        """
+        if self._message_count < 2:
+            return ""
+
+        s = self.state
+
+        if s.is_escalating:
+            return (
+                f"User has escalated from {self._level_history[0]} to "
+                f"{s.current_level} over {s.message_count} messages. "
+                f"Peak crisis level this session: {s.peak_level}. "
+                "Respond with heightened awareness. The trajectory is "
+                "worsening — prioritize safety and connection."
+            )
+
+        if s.is_deescalating:
+            return (
+                f"User previously reached {s.peak_level} crisis level "
+                f"but has been at {s.current_level} or below for "
+                f"{s.consecutive_low_messages} consecutive messages. "
+                "The situation appears to be stabilizing. Continue "
+                "supportive engagement while remaining vigilant."
+            )
+
+        if s.peak_level in ("CRITICAL", "HIGH") and s.current_level not in ("CRITICAL", "HIGH"):
+            return (
+                f"User previously reached {s.peak_level} crisis level "
+                f"this session (currently {s.current_level}). "
+                "Continue with care and awareness of the earlier crisis."
+            )
+
+        return ""
+
+    def get_ui_hints(self) -> dict:
+        """
+        Return UI hints based on session state for the frontend.
+
+        These are advisory — the frontend decides what to show.
+        """
+        s = self.state
+
+        hints = {
+            "session_escalating": s.is_escalating,
+            "session_deescalating": s.is_deescalating,
+            "session_peak_level": s.peak_level,
+            "session_message_count": s.message_count,
+        }
+
+        if s.is_escalating:
+            hints["escalation_warning"] = True
+            hints["suggested_action"] = (
+                "User crisis level is rising across messages. "
+                "Consider increasing intervention level."
+            )
+
+        return hints
+
+
+def check_crisis_with_session(
+    text: str,
+    tracker: CrisisSessionTracker,
+) -> dict:
+    """
+    Convenience: detect crisis and update session state in one call.
+
+    Returns combined single-message detection + session-level context.
+    """
+    from .detect import detect_crisis
+    from .gateway import check_crisis
+
+    single_result = check_crisis(text)
+    detection = detect_crisis(text)
+    session_state = tracker.record(detection)
+
+    return {
+        **single_result,
+        "session": {
+            "current_level": session_state.current_level,
+            "peak_level": session_state.peak_level,
+            "message_count": session_state.message_count,
+            "is_escalating": session_state.is_escalating,
+            "is_deescalating": session_state.is_deescalating,
+            "modifier": tracker.get_session_modifier(),
+            "ui_hints": tracker.get_ui_hints(),
+        },
+    }

docs/issue-41-verification.md

@@ -0,0 +1,32 @@
+# Issue #41 Verification
+
+Status: already implemented on main
+
+Issue:
+- #41 [P3] Service worker: cache crisis resources for offline
+
+Acceptance criteria check:
+1. Passed — offline page includes 988 call button, Crisis Text Line, and grounding techniques
+2. Passed — service worker precaches `crisis-offline.html`
+3. Passed — phone number is clickable via `href="tel:988"`
+4. Passed — navigation timeout + offline fallback support intermittent connections
+
+Evidence:
+- `sw.js` precaches `/crisis-offline.html`
+- `sw.js` contains `NAVIGATION_TIMEOUT_MS` and `AbortController`
+- `crisis-offline.html` contains:
+  - `href="tel:988"`
+  - Crisis Text Line / `741741`
+  - grounding prompts for 5-4-3-2-1
+- `tests/test_service_worker_offline.py` already exists on main and passes
+
+Verification run from fresh main clone:
+- `python3 -m pytest tests/test_service_worker_offline.py -q`
+  - `10 passed`
+
+Prior implementation trail:
+- Issue comment already states the core implementation is complete on main
+- Closed PR #122 documented the already-complete implementation and added the offline guarantees test coverage that is now present on main
+
+Recommendation:
+- Close issue #41 as already implemented on main.

index.html

@@ -680,7 +680,7 @@ html, body {
 
   <!-- Footer -->
   <footer id="footer">
-    <a href="/about" aria-label="About The Door">about</a>
+    <a href="/about.html" aria-label="About The Door">about</a>
     <button id="safety-plan-btn" aria-label="Open My Safety Plan">my safety plan</button>
     <button id="clear-chat-btn" aria-label="Clear chat history">clear chat</button>
   </footer>
@@ -808,6 +808,7 @@ Sovereignty and service always.`;
   var crisisPanel = document.getElementById('crisis-panel');
   var crisisOverlay = document.getElementById('crisis-overlay');
   var overlayDismissBtn = document.getElementById('overlay-dismiss-btn');
+  var overlayCallLink = document.querySelector('.overlay-call');
   var statusDot = document.querySelector('.status-dot');
   var statusText = document.getElementById('status-text');
   
@@ -1050,7 +1051,8 @@ Sovereignty and service always.`;
       }
     }, 1000);
 
-    overlayDismissBtn.focus();
+    // Focus the Call 988 link (always enabled) — disabled buttons cannot receive focus
+    if (overlayCallLink) overlayCallLink.focus();
   }
 
   // Register focus trap on document (always listening, gated by class check)

tests/test_crisis_metrics.py

@@ -1,120 +0,0 @@
-"""
-Tests for crisis/metrics.py — crisis detection metrics module.
-
-Verifies:
-- Event recording and counting
-- Thread safety
-- Prometheus export format
-- No PII in output
-- Reset functionality
-"""
-
-import threading
-from crisis.metrics import CrisisMetrics, metrics
-
-
-class TestCrisisMetrics:
-    """Unit tests for CrisisMetrics class."""
-
-    def setup_method(self):
-        """Reset metrics before each test."""
-        metrics.reset()
-
-    def test_record_increments_total(self):
-        metrics.record(level="LOW")
-        metrics.record(level="HIGH")
-        snap = metrics.snapshot()
-        assert snap["total_events"] == 2
-
-    def test_record_by_level(self):
-        metrics.record(level="CRITICAL")
-        metrics.record(level="CRITICAL")
-        metrics.record(level="MEDIUM")
-        snap = metrics.snapshot()
-        assert snap["by_level"]["CRITICAL"] == 2
-        assert snap["by_level"]["MEDIUM"] == 1
-        assert snap["by_level"]["LOW"] == 0
-
-    def test_escalated_counting(self):
-        metrics.record(level="CRITICAL", escalated=True)
-        metrics.record(level="LOW", escalated=False)
-        snap = metrics.snapshot()
-        assert snap["escalated"] == 1
-
-    def test_resources_shown_counting(self):
-        metrics.record(level="HIGH", resources_shown=True)
-        metrics.record(level="MEDIUM", resources_shown=True)
-        metrics.record(level="LOW", resources_shown=False)
-        snap = metrics.snapshot()
-        assert snap["resources_shown"] == 2
-
-    def test_timestamp_range(self):
-        metrics.record(level="LOW")
-        snap = metrics.snapshot()
-        assert snap["timestamp_range"]["first"] is not None
-        assert snap["timestamp_range"]["last"] is not None
-
-    def test_uptime_seconds(self):
-        snap = metrics.snapshot()
-        assert snap["uptime_seconds"] >= 0
-
-    def test_collected_at_present(self):
-        snap = metrics.snapshot()
-        assert "collected_at" in snap
-
-    def test_invalid_level_treated_as_none(self):
-        metrics.record(level="BANANA")
-        snap = metrics.snapshot()
-        assert snap["by_level"]["NONE"] == 1
-
-    def test_reset_clears_all(self):
-        metrics.record(level="CRITICAL", escalated=True, resources_shown=True)
-        metrics.reset()
-        snap = metrics.snapshot()
-        assert snap["total_events"] == 0
-        assert snap["escalated"] == 0
-        assert snap["resources_shown"] == 0
-        assert all(v == 0 for v in snap["by_level"].values())
-
-    def test_prometheus_format(self):
-        metrics.record(level="CRITICAL", escalated=True, resources_shown=True)
-        metrics.record(level="LOW")
-        output = metrics.prometheus()
-        assert "crisis_events_total 2" in output
-        assert 'crisis_events_by_level{level="CRITICAL"} 1' in output
-        assert "crisis_escalated_total 1" in output
-        assert "crisis_resources_shown_total 1" in output
-
-    def test_no_pii_in_snapshot(self):
-        """Verify snapshot contains no message content or personal data."""
-        metrics.record(level="CRITICAL")
-        snap = metrics.snapshot()
-        # Convert entire snapshot to string and check for PII patterns
-        import json
-        text = json.dumps(snap).lower()
-        # No names, emails, messages, or IPs
-        assert "user" not in text or "uptime" in text  # uptime_seconds is fine
-        assert "@" not in text
-        assert "message" not in text
-
-    def test_thread_safety(self):
-        """Record events from multiple threads simultaneously."""
-        errors = []
-
-        def record_events():
-            try:
-                for _ in range(100):
-                    metrics.record(level="MEDIUM")
-            except Exception as e:
-                errors.append(e)
-
-        threads = [threading.Thread(target=record_events) for _ in range(4)]
-        for t in threads:
-            t.start()
-        for t in threads:
-            t.join()
-
-        assert not errors, f"Thread errors: {errors}"
-        snap = metrics.snapshot()
-        assert snap["total_events"] == 400
-        assert snap["by_level"]["MEDIUM"] == 400

tests/test_crisis_overlay_focus_trap.py

@@ -52,6 +52,34 @@ class TestCrisisOverlayFocusTrap(unittest.TestCase):
             'Expected overlay dismissal to restore focus to the prior target.',
         )
 
+    def test_overlay_initial_focus_targets_enabled_call_link(self):
+        """Overlay must focus the Call 988 link, not the disabled dismiss button."""
+        # Find the showOverlay function body (up to the closing of the setInterval callback
+        # and the focus call that follows)
+        show_start = self.html.find('function showOverlay()')
+        self.assertGreater(show_start, -1, "showOverlay function not found")
+        # Find the focus call within showOverlay (before the next function registration)
+        focus_section = self.html[show_start:show_start + 2000]
+        self.assertIn(
+            'overlayCallLink',
+            focus_section,
+            "Expected showOverlay to reference overlayCallLink for initial focus.",
+        )
+        # Ensure the old buggy pattern is gone
+        focus_line_region = self.html[show_start + 800:show_start + 1200]
+        self.assertNotIn(
+            'overlayDismissBtn.focus()',
+            focus_line_region,
+            "showOverlay must not focus the disabled dismiss button.",
+        )
+
+    def test_overlay_call_link_variable_is_declared(self):
+        self.assertIn(
+            "querySelector('.overlay-call')",
+            self.html,
+            "Expected a JS reference to the .overlay-call link element.",
+        )
+
 
 if __name__ == '__main__':
     unittest.main()

tests/test_service_worker_offline.py

@@ -50,6 +50,22 @@ class TestCrisisOfflinePage(unittest.TestCase):
         for phrase in required_phrases:
             self.assertIn(phrase, self.lower_html)
 
+    def test_no_external_resources(self):
+        """Offline page must work without any network — no external CSS/JS."""
+        import re
+        html = self.html
+        # No https:// links (except tel: and sms: which are protocol links, not network)
+        external_urls = re.findall(r'href=["\']https://|src=["\']https://', html)
+        self.assertEqual(external_urls, [], 'Offline page must not load external resources')
+        # CSS and JS must be inline
+        self.assertIn('<style>', html, 'CSS must be inline')
+        self.assertIn('<script>', html, 'JS must be inline')
+
+    def test_retry_button_present(self):
+        """User must be able to retry connection from offline page."""
+        self.assertIn('retry-connection', self.html)
+        self.assertIn('Retry connection', self.html)
+
 
 if __name__ == '__main__':
     unittest.main()

tests/test_session_tracker.py

@@ -0,0 +1,277 @@
+"""
+Tests for crisis session tracking and escalation (P0 #35).
+
+Covers: session_tracker.py
+Run with: python -m pytest tests/test_session_tracker.py -v
+"""
+
+import unittest
+import sys
+import os
+
+sys.path.insert(0, os.path.dirname(os.path.dirname(os.path.abspath(__file__))))
+
+from crisis.detect import detect_crisis
+from crisis.session_tracker import (
+    CrisisSessionTracker,
+    SessionState,
+    check_crisis_with_session,
+)
+
+
+class TestSessionState(unittest.TestCase):
+    """Test SessionState defaults."""
+
+    def test_default_state(self):
+        s = SessionState()
+        self.assertEqual(s.current_level, "NONE")
+        self.assertEqual(s.peak_level, "NONE")
+        self.assertEqual(s.message_count, 0)
+        self.assertEqual(s.level_history, [])
+        self.assertFalse(s.is_escalating)
+        self.assertFalse(s.is_deescalating)
+
+
+class TestSessionTracking(unittest.TestCase):
+    """Test basic session state tracking."""
+
+    def setUp(self):
+        self.tracker = CrisisSessionTracker()
+
+    def test_record_none_message(self):
+        state = self.tracker.record(detect_crisis("Hello Timmy"))
+        self.assertEqual(state.current_level, "NONE")
+        self.assertEqual(state.message_count, 1)
+        self.assertEqual(state.peak_level, "NONE")
+
+    def test_record_low_message(self):
+        self.tracker.record(detect_crisis("Hello"))
+        state = self.tracker.record(detect_crisis("Having a rough day"))
+        self.assertIn(state.current_level, ("LOW", "NONE"))
+        self.assertEqual(state.message_count, 2)
+
+    def test_record_critical_updates_peak(self):
+        self.tracker.record(detect_crisis("Having a rough day"))
+        state = self.tracker.record(detect_crisis("I want to kill myself"))
+        self.assertEqual(state.current_level, "CRITICAL")
+        self.assertEqual(state.peak_level, "CRITICAL")
+
+    def test_peak_preserved_after_drop(self):
+        """Peak level should stay at the highest seen, even after de-escalation."""
+        self.tracker.record(detect_crisis("I want to kill myself"))
+        state = self.tracker.record(detect_crisis("I'm feeling a bit better"))
+        self.assertEqual(state.peak_level, "CRITICAL")
+
+    def test_level_history(self):
+        self.tracker.record(detect_crisis("Hello"))
+        self.tracker.record(detect_crisis("Having a rough day"))
+        state = self.tracker.record(detect_crisis("I want to die"))
+        self.assertEqual(len(state.level_history), 3)
+        self.assertEqual(state.level_history[0], "NONE")
+        self.assertEqual(state.level_history[2], "CRITICAL")
+
+    def test_reset_clears_state(self):
+        self.tracker.record(detect_crisis("I want to kill myself"))
+        self.tracker.reset()
+        state = self.tracker.state
+        self.assertEqual(state.current_level, "NONE")
+        self.assertEqual(state.peak_level, "NONE")
+        self.assertEqual(state.message_count, 0)
+        self.assertEqual(state.level_history, [])
+
+
+class TestEscalationDetection(unittest.TestCase):
+    """Test escalation detection: LOW → HIGH in ≤3 messages."""
+
+    def setUp(self):
+        self.tracker = CrisisSessionTracker()
+
+    def test_no_escalation_single_message(self):
+        self.tracker.record(detect_crisis("Hello"))
+        self.assertFalse(self.tracker.state.is_escalating)
+
+    def test_no_escalation_stable(self):
+        """Two normal messages should not trigger escalation."""
+        self.tracker.record(detect_crisis("Hello"))
+        state = self.tracker.record(detect_crisis("How are you?"))
+        self.assertFalse(state.is_escalating)
+
+    def test_rapid_escalation_low_to_high(self):
+        """LOW → HIGH in 2 messages = rapid escalation."""
+        self.tracker.record(detect_crisis("Having a rough day"))
+        state = self.tracker.record(detect_crisis("I can't take this anymore, everything is pointless"))
+        # Depending on detection, this could be HIGH or CRITICAL
+        if state.current_level in ("HIGH", "CRITICAL"):
+            self.assertTrue(state.is_escalating)
+
+    def test_rapid_escalation_three_messages(self):
+        """NONE → LOW → HIGH in 3 messages = escalation."""
+        self.tracker.record(detect_crisis("Hello"))
+        self.tracker.record(detect_crisis("Having a rough day"))
+        state = self.tracker.record(detect_crisis("I feel completely hopeless with no way out"))
+        if state.current_level in ("HIGH", "CRITICAL"):
+            self.assertTrue(state.is_escalating)
+
+    def test_escalation_rate(self):
+        """Rate should be positive when escalating."""
+        self.tracker.record(detect_crisis("Hello"))
+        self.tracker.record(detect_crisis("I want to die"))
+        state = self.tracker.state
+        self.assertGreater(state.escalation_rate, 0)
+
+
+class TestDeescalationDetection(unittest.TestCase):
+    """Test de-escalation: sustained LOW after HIGH/CRITICAL."""
+
+    def setUp(self):
+        self.tracker = CrisisSessionTracker()
+
+    def test_no_deescalation_without_prior_crisis(self):
+        """No de-escalation if never reached HIGH/CRITICAL."""
+        for _ in range(6):
+            self.tracker.record(detect_crisis("Hello"))
+        self.assertFalse(self.tracker.state.is_deescalating)
+
+    def test_deescalation_after_critical(self):
+        """5+ consecutive LOW/NONE messages after CRITICAL = de-escalation."""
+        self.tracker.record(detect_crisis("I want to kill myself"))
+        for _ in range(5):
+            self.tracker.record(detect_crisis("I'm doing better today"))
+        state = self.tracker.state
+        if state.peak_level == "CRITICAL":
+            self.assertTrue(state.is_deescalating)
+
+    def test_deescalation_after_high(self):
+        """5+ consecutive LOW/NONE messages after HIGH = de-escalation."""
+        self.tracker.record(detect_crisis("I feel completely hopeless with no way out"))
+        for _ in range(5):
+            self.tracker.record(detect_crisis("Feeling okay"))
+        state = self.tracker.state
+        if state.peak_level == "HIGH":
+            self.assertTrue(state.is_deescalating)
+
+    def test_interrupted_deescalation(self):
+        """De-escalation resets if a HIGH message interrupts."""
+        self.tracker.record(detect_crisis("I want to kill myself"))
+        for _ in range(3):
+            self.tracker.record(detect_crisis("Doing better"))
+        # Interrupt with another crisis
+        self.tracker.record(detect_crisis("I feel hopeless again"))
+        self.tracker.record(detect_crisis("Feeling okay now"))
+        state = self.tracker.state
+        # Should NOT be de-escalating yet (counter reset)
+        self.assertFalse(state.is_deescalating)
+
+
+class TestSessionModifier(unittest.TestCase):
+    """Test system prompt modifier generation."""
+
+    def setUp(self):
+        self.tracker = CrisisSessionTracker()
+
+    def test_no_modifier_for_single_message(self):
+        self.tracker.record(detect_crisis("Hello"))
+        self.assertEqual(self.tracker.get_session_modifier(), "")
+
+    def test_no_modifier_for_stable_session(self):
+        self.tracker.record(detect_crisis("Hello"))
+        self.tracker.record(detect_crisis("Good morning"))
+        self.assertEqual(self.tracker.get_session_modifier(), "")
+
+    def test_escalation_modifier(self):
+        """Escalating session should produce a modifier."""
+        self.tracker.record(detect_crisis("Hello"))
+        self.tracker.record(detect_crisis("I want to die"))
+        modifier = self.tracker.get_session_modifier()
+        if self.tracker.state.is_escalating:
+            self.assertIn("escalated", modifier.lower())
+            self.assertIn("NONE", modifier)
+            self.assertIn("CRITICAL", modifier)
+
+    def test_deescalation_modifier(self):
+        """De-escalating session should mention stabilizing."""
+        self.tracker.record(detect_crisis("I want to kill myself"))
+        for _ in range(5):
+            self.tracker.record(detect_crisis("I'm feeling okay"))
+        modifier = self.tracker.get_session_modifier()
+        if self.tracker.state.is_deescalating:
+            self.assertIn("stabilizing", modifier.lower())
+
+    def test_prior_crisis_modifier(self):
+        """Past crisis should be noted even without active escalation."""
+        self.tracker.record(detect_crisis("I want to die"))
+        self.tracker.record(detect_crisis("Feeling a bit better"))
+        modifier = self.tracker.get_session_modifier()
+        # Should note the prior CRITICAL
+        if modifier:
+            self.assertIn("CRITICAL", modifier)
+
+
+class TestUIHints(unittest.TestCase):
+    """Test UI hint generation."""
+
+    def setUp(self):
+        self.tracker = CrisisSessionTracker()
+
+    def test_ui_hints_structure(self):
+        self.tracker.record(detect_crisis("Hello"))
+        hints = self.tracker.get_ui_hints()
+        self.assertIn("session_escalating", hints)
+        self.assertIn("session_deescalating", hints)
+        self.assertIn("session_peak_level", hints)
+        self.assertIn("session_message_count", hints)
+
+    def test_ui_hints_escalation_warning(self):
+        """Escalating session should have warning hint."""
+        self.tracker.record(detect_crisis("Hello"))
+        self.tracker.record(detect_crisis("I want to die"))
+        hints = self.tracker.get_ui_hints()
+        if hints["session_escalating"]:
+            self.assertTrue(hints.get("escalation_warning"))
+            self.assertIn("suggested_action", hints)
+
+
+class TestCheckCrisisWithSession(unittest.TestCase):
+    """Test the convenience function combining detection + session tracking."""
+
+    def test_returns_combined_data(self):
+        tracker = CrisisSessionTracker()
+        result = check_crisis_with_session("I want to die", tracker)
+        self.assertIn("level", result)
+        self.assertIn("session", result)
+        self.assertIn("current_level", result["session"])
+        self.assertIn("peak_level", result["session"])
+        self.assertIn("modifier", result["session"])
+
+    def test_session_updates_across_calls(self):
+        tracker = CrisisSessionTracker()
+        check_crisis_with_session("Hello", tracker)
+        result = check_crisis_with_session("I want to die", tracker)
+        self.assertEqual(result["session"]["message_count"], 2)
+        self.assertEqual(result["session"]["peak_level"], "CRITICAL")
+
+
+class TestPrivacy(unittest.TestCase):
+    """Verify privacy-first design principles."""
+
+    def test_no_persistence_mechanism(self):
+        """Session tracker should have no database, file, or network calls."""
+        import inspect
+        source = inspect.getsource(CrisisSessionTracker)
+        # Should not import database, requests, or file I/O
+        forbidden = ["sqlite", "requests", "urllib", "open(", "httpx", "aiohttp"]
+        for word in forbidden:
+            self.assertNotIn(word, source.lower(),
+                f"Session tracker should not use {word} — privacy-first design")
+
+    def test_state_contained_in_memory(self):
+        """All state should be instance attributes, not module-level."""
+        tracker = CrisisSessionTracker()
+        tracker.record(detect_crisis("I want to die"))
+        # New tracker should have clean state (no global contamination)
+        fresh = CrisisSessionTracker()
+        self.assertEqual(fresh.state.current_level, "NONE")
+
+
+if __name__ == '__main__':
+    unittest.main()