Merge pull request #121 from nesquena/feat/self-update-checker

feat: self-update checker with one-click update

CHANGELOG.md

@@ -5,6 +5,60 @@
 
 ---
 
+## [v0.36] Self-Update Checker with One-Click Update
+*April 5, 2026 | 433 tests*
+
+### Features
+- **Update checker.** Non-blocking background check on boot detects when the
+  WebUI or hermes-agent git repos are behind upstream. Blue banner shows
+  "WebUI: N updates, Agent: N updates available" with Update Now / Later.
+- **One-click update.** "Update Now" runs `git stash && git pull --ff-only &&
+  git stash pop` on each behind repo, then reloads the page. Concurrent update
+  attempts blocked via lock. Dirty working trees safely stashed and restored.
+- **Settings toggle.** "Check for updates" checkbox in Settings panel. Persisted
+  server-side. Disabled = no background fetch, no banner.
+- **30-minute cache.** Git fetch runs at most twice per hour regardless of tab
+  count. Results cached server-side with TTL.
+- **Session-scoped dismissal.** "Later" dismisses banner for the current tab
+  session (sessionStorage). New tabs get a fresh check.
+- **Test mode.** `?test_updates=1` URL param shows the banner with fake data
+  (localhost only) for UI testing without needing to actually be behind.
+
+### Architecture
+- New `api/updates.py`: `check_for_updates()`, `apply_update()`. Thread-safe
+  caching with `_cache_lock`. Concurrent apply blocked with `_apply_lock`.
+  Default branch auto-detected (master/main).
+- `api/routes.py`: `GET /api/updates/check`, `POST /api/updates/apply`.
+  Simulate endpoint gated to 127.0.0.1.
+- `static/ui.js`: `_showUpdateBanner()`, `dismissUpdate()`, `applyUpdates()`.
+- `static/boot.js`: fire-and-forget check on boot (does not block UI).
+- `api/config.py`: `check_for_updates` in settings defaults + bool keys.
+- Docker safe: all git ops gated by `.git` directory existence check.
+
+---
+
+## [v0.35.1] Model dropdown fixes
+*April 5, 2026 | 433 tests*
+
+### Bug Fixes
+- **Custom providers invisible in model dropdown (#117).** `cfg_base_url` was scoped inside a conditional block but referenced unconditionally, causing a `NameError` for users with a `base_url` in config.yaml. Fix: initialize to `''` before the block. (#118)
+- **Configured default model missing from dropdown (#116).** OpenRouter and other providers replaced the model list with a hardcoded fallback that didn't include `model.default` values like `openrouter/free` or custom local model names. Fix: after building all groups, inject the configured `default_model` at the top of its provider group if absent. (#119)
+
+---
+
+## [v0.35] Security hardening
+*April 5, 2026 | 433 tests*
+
+### Security fixes
+- **ENV race condition (HIGH):** Two concurrent sessions could interleave `os.environ` writes, clobbering workspace and session keys. Fixed with a global `_ENV_LOCK` in `streaming.py` that serializes the env save/restore block across all sessions. (#108)
+- **Predictable signing key (MEDIUM):** Session cookies were signed with `sha256(STATE_DIR)` -- deterministic and forgeable if the install path is known. Now generates a cryptographically random 32-byte key on first startup, persisted to `STATE_DIR/.signing_key` (chmod 600). (#108)
+- **Upload path traversal (MEDIUM):** Filenames like `..` survived the `[^\w.\-]` sanitization regex because dots are allowed. Fixed by rejecting dot-only filenames and validating the resolved path stays within the workspace sandbox via `safe_resolve_ws()`. (#108)
+- **Weak password hashing (MEDIUM):** Bare SHA-256 with a predictable salt replaced with PBKDF2-SHA256 at 600k iterations (OWASP recommendation) using the random signing key as salt. No new dependencies (stdlib `hashlib.pbkdf2_hmac`). (#108)
+
+**Breaking change:** Existing session cookies and password hashes are invalidated on first restart after upgrade. Users with password auth enabled will need to re-set their password.
+
+---
+
 ## [v0.34.3] Light theme final polish
 *April 5, 2026 | 433 tests*
 
@@ -1214,4 +1268,4 @@ Three-panel layout: sessions sidebar, chat area, workspace panel.
 
 ---
 
-*Last updated: v0.34, April 5, 2026 | Tests: 433*
+*Last updated: v0.36, April 5, 2026 | Tests: 433*

README.md

@@ -10,7 +10,20 @@ and vanilla JS.
 Layout: three-panel Claude-style. Left sidebar for sessions and tools,
 center for chat, right for workspace file browsing.
 
-<img width="1392" alt="Hermes Web UI — three-panel layout" src="https://github.com/user-attachments/assets/79cd3c0d-3167-42ed-9434-447a742c25c3" />
+<img alt="Hermes Web UI — three-panel layout" width="1417" height="867" alt="image" src="https://github.com/user-attachments/assets/51adff98-53ee-4800-8508-78b6c34dd3dc" />
+
+<table>
+  <tr>
+    <td width="50%" align="center">
+      <img alt="Light mode with full profile support" src="https://github.com/user-attachments/assets/9b68142f-d974-4493-a8d1-fd73e622c7fd" />
+      <br /><sub>Light mode with full profile support</sub>
+    </td>
+    <td width="50%" align="center">
+      <img alt="Customize your settings, configure a password" src="https://github.com/user-attachments/assets/941f3156-21e3-41fd-bcc8-f975d5000cb8" />
+      <br /><sub>Customize your settings, configure a password</sub>
+    </td>
+  </tr>
+</table>
 
 <table>
   <tr>
@@ -202,6 +215,40 @@ are running over SSH.
 
 ---
 
+## Accessing on your phone with Tailscale
+
+[Tailscale](https://tailscale.com) is a zero-config mesh VPN built on
+WireGuard. Install it on your server and your phone, and they join the same
+private network -- no port forwarding, no SSH tunnels, no public exposure.
+
+The Hermes Web UI is fully responsive with a mobile-optimized layout
+(hamburger sidebar, bottom navigation bar, touch-friendly controls), so it
+works well as a daily-driver agent interface from your phone.
+
+**Setup:**
+
+1. Install [Tailscale](https://tailscale.com/download) on your server and
+   your iPhone/Android.
+2. Start the WebUI listening on all interfaces with password auth enabled:
+
+```bash
+HERMES_WEBUI_HOST=0.0.0.0 HERMES_WEBUI_PASSWORD=your-secret ./start.sh
+```
+
+3. Open `http://<server-tailscale-ip>:8787` in your phone's browser
+   (find your server's Tailscale IP in the Tailscale app or with
+   `tailscale ip -4` on the server).
+
+That's it. Traffic is encrypted end-to-end by WireGuard, and password auth
+protects the UI at the application level. You can add it to your home screen
+for an app-like experience.
+
+> **Tip:** If using Docker, set `HERMES_WEBUI_HOST=0.0.0.0` in your
+> `docker-compose.yml` environment (already the default) and set
+> `HERMES_WEBUI_PASSWORD`.
+
+---
+
 ## Manual launch (without start.sh)
 
 If you prefer to launch the server directly:

ROADMAP.md

@@ -3,8 +3,8 @@
 > Goal: Full 1:1 parity with the Hermes CLI experience via a clean dark web UI.
 > Everything you can do from the CLI terminal, you can do from this UI.
 >
-> Last updated: v0.33 (April 5, 2026)
-> Tests: 424 total (424 passing, 0 failures)
+> Last updated: v0.35 (April 5, 2026)
+> Tests: 433 total (433 passing, 0 failures)
 > Source: <repo>/
 
 ---
@@ -42,6 +42,11 @@
 | Sprint 23 | Agentic transparency | Token/cost display, subagent cards, skill picker in cron, skill linked files, workspace tree persistence, timestamp fixes | 424 |
 | v0.32 | Auto-compaction handling | Compression detection, /compact command, real context window indicator | 424 |
 | v0.33 | /insights sync | Opt-in state.db sync so `hermes /insights` includes WebUI sessions | 424 |
+| v0.34 | Sprint 26 — Pluggable themes | Dark, Light, Slate, Solarized, Monokai, Nord; settings unsaved-changes guard; /theme command | 433 |
+| v0.34.1 | Theme variable polish | 30+ hardcoded dark-navy colors replaced with theme-aware CSS variables | 433 |
+| v0.34.2 | Theme text colors | 5 new per-theme typography variables (--strong, --em, --code-text, --code-inline-bg, --pre-text) | 433 |
+| v0.34.3 | Light theme final polish | 46 light-scoped selector overrides for sidebar, roles, chips, interactive elements | 433 |
+| v0.35 | Security hardening | Env race fix, random signing key, upload path traversal, PBKDF2 password hash | 433 |
 
 ---
 
@@ -209,7 +214,7 @@
 - [x] Background task cancel (activity bar Cancel button)
 - [ ] Code execution cell (deferred)
 - [ ] Desktop application (Sprint 25, PLANNED)
-- [ ] Pluggable UI themes -- light, dark, Solarized, Monokai, Nord (Sprint 26, PLANNED)
+- [x] Pluggable UI themes -- Dark, Light, Slate, Solarized, Monokai, Nord (Sprint 26, v0.34)
 - [ ] Extended slash command / skill integration (deferred)
 - [ ] Virtual scroll for large lists (deferred)
 

SPRINTS.md

@@ -1,6 +1,6 @@
 # Hermes Web UI -- Forward Sprint Plan
 
-> Current state: v0.34 | 433 tests | Daily driver ready
+> Current state: v0.36 | 433 tests | Daily driver ready
 > This document plans the path from here to two targets:
 >
 > Target A: 1:1 feature parity with the Hermes CLI (everything you can do from the
@@ -893,7 +893,7 @@ genuinely differentiating for an open-source project
 
 ---
 
-## Sprint 26 -- Pluggable UI Themes (PLANNED)
+## Sprint 26 -- Pluggable UI Themes (COMPLETED)
 
 **Theme:** Let users choose how the app looks -- light, dark, and custom color
 schemes. One-click switching, persistent preference, zero flicker on load.
@@ -1156,6 +1156,6 @@ New test cases in `tests/test_sprint26.py`:
 ---
 
 *Last updated: April 5, 2026*
-*Current version: v0.34 | 433 tests*
+*Current version: v0.36 | 433 tests*
 *Next sprint: Sprint 24 (Web Polish + Bug Fix Pass)*
-*Horizon sprint: Sprint 26 (Pluggable UI Themes)*
+*Horizon sprint: Sprint 25 (macOS Desktop Application)*

TESTING.md

@@ -1,14 +1,14 @@
 # Hermes Web UI: Browser Testing Plan
 
 > This document is for manual browser testing by you or by a Claude browser agent.
-> It covers user-facing features of the UI through Sprint 22 (v0.24).
+> It covers user-facing features of the UI through Sprint 26 (v0.34.3).
 > Each section is written as a step-by-step test procedure with expected outcomes.
 > A browser agent (e.g. Claude with Chrome access) can execute this plan directly.
 >
-> Prerequisites: SSH tunnel is active on port 8787. Open http://localhost:8787 in browser.
-> Server health check: curl http://127.0.0.1:8787/health should return {"status":"ok"}.
+> Prerequisites: SSH tunnel is active on port 8786. Open http://localhost:8786 in browser.
+> Server health check: curl http://127.0.0.1:8786/health should return {"status":"ok"}.
 >
-> Automated tests: 424 total (424 passing, 0 failures)
+> Automated tests: 433 total (433 passing, 0 failures)
 > Run: `pytest tests/ -v --timeout=60`
 
 ---
@@ -1708,8 +1708,8 @@ Each has automated API-level tests in `tests/test_sprint{N}.py`.
 
 ---
 
-*Last updated: Sprint 22 / v0.24, April 3, 2026*
-*Total automated tests: 415 (392 passing, 23 pre-existing failures)*
-*Regression gate: tests/test_regressions.py (23 tests)*
+*Last updated: Sprint 26 / v0.34.3, April 5, 2026*
+*Total automated tests: 433 (433 passing, 0 failures)*
+*Regression gate: tests/test_regressions.py*
 *Run: pytest tests/ -v --timeout=60*
 *Source: <repo>/*

api/auth.py

@@ -26,17 +26,38 @@ _sessions = {}
 
 
 def _signing_key():
-    """Derive a stable signing key from STATE_DIR."""
-    return hashlib.sha256(str(STATE_DIR).encode()).digest()
+    """Return a random signing key, generating and persisting one on first call."""
+    key_file = STATE_DIR / '.signing_key'
+    if key_file.exists():
+        try:
+            raw = key_file.read_bytes()
+            if len(raw) >= 32:
+                return raw[:32]
+        except Exception:
+            pass
+    # Generate a new random key
+    key = secrets.token_bytes(32)
+    try:
+        STATE_DIR.mkdir(parents=True, exist_ok=True)
+        key_file.write_bytes(key)
+        key_file.chmod(0o600)
+    except Exception:
+        pass  # key works for this process even if persist fails
+    return key
 
 
 def _hash_password(password):
-    """SHA-256 hash with a salt derived from STATE_DIR."""
-    salt = str(STATE_DIR).encode()
-    return hashlib.sha256(salt + password.encode()).hexdigest()
+    """PBKDF2-SHA256 with 600k iterations (OWASP recommendation).
+    Salt is the persisted random signing key, which is secret and unique per
+    installation. This keeps the stored hash format a plain hex string
+    (no format change to settings.json) while replacing the predictable
+    STATE_DIR-derived salt from the original implementation."""
+    salt = _signing_key()
+    dk = hashlib.pbkdf2_hmac('sha256', password.encode(), salt, 600_000)
+    return dk.hex()
 
 
-def get_password_hash():
+def get_password_hash() -> str | None:
     """Return the active password hash, or None if auth is disabled.
     Priority: env var > settings.json."""
     env_pw = os.getenv('HERMES_WEBUI_PASSWORD', '').strip()
@@ -46,12 +67,12 @@ def get_password_hash():
     return settings.get('password_hash') or None
 
 
-def is_auth_enabled():
+def is_auth_enabled() -> bool:
     """True if a password is configured (env var or settings)."""
     return get_password_hash() is not None
 
 
-def verify_password(plain):
+def verify_password(plain) -> bool:
     """Verify a plaintext password against the stored hash."""
     expected = get_password_hash()
     if not expected:
@@ -59,7 +80,7 @@ def verify_password(plain):
     return hmac.compare_digest(_hash_password(plain), expected)
 
 
-def create_session():
+def create_session() -> str:
     """Create a new auth session. Returns signed cookie value."""
     token = secrets.token_hex(32)
     _sessions[token] = time.time() + SESSION_TTL
@@ -67,7 +88,7 @@ def create_session():
     return f"{token}.{sig}"
 
 
-def verify_session(cookie_value):
+def verify_session(cookie_value) -> bool:
     """Verify a signed session cookie. Returns True if valid and not expired."""
     if not cookie_value or '.' not in cookie_value:
         return False
@@ -82,14 +103,14 @@ def verify_session(cookie_value):
     return True
 
 
-def invalidate_session(cookie_value):
+def invalidate_session(cookie_value) -> None:
     """Remove a session token."""
     if cookie_value and '.' in cookie_value:
         token = cookie_value.rsplit('.', 1)[0]
         _sessions.pop(token, None)
 
 
-def parse_cookie(handler):
+def parse_cookie(handler) -> str | None:
     """Extract the auth cookie from the request headers."""
     cookie_header = handler.headers.get('Cookie', '')
     if not cookie_header:
@@ -103,7 +124,7 @@ def parse_cookie(handler):
     return morsel.value if morsel else None
 
 
-def check_auth(handler, parsed):
+def check_auth(handler, parsed) -> bool:
     """Check if request is authorized. Returns True if OK.
     If not authorized, sends 401 (API) or 302 redirect (page) and returns False."""
     if not is_auth_enabled():
@@ -128,7 +149,7 @@ def check_auth(handler, parsed):
     return False
 
 
-def set_auth_cookie(handler, cookie_value):
+def set_auth_cookie(handler, cookie_value) -> None:
     """Set the auth cookie on the response."""
     cookie = http.cookies.SimpleCookie()
     cookie[COOKIE_NAME] = cookie_value
@@ -139,7 +160,7 @@ def set_auth_cookie(handler, cookie_value):
     handler.send_header('Set-Cookie', cookie[COOKIE_NAME].OutputString())
 
 
-def clear_auth_cookie(handler):
+def clear_auth_cookie(handler) -> None:
     """Clear the auth cookie on the response."""
     cookie = http.cookies.SimpleCookie()
     cookie[COOKIE_NAME] = ''

api/config.py

@@ -169,7 +169,7 @@ def get_config() -> dict:
         reload_config()
     return _cfg_cache
 
-def reload_config():
+def reload_config() -> None:
     """Reload config.yaml from the active profile's directory."""
     with _cfg_lock:
         _cfg_cache.clear()
@@ -208,7 +208,7 @@ DEFAULT_WORKSPACE = _discover_default_workspace()
 DEFAULT_MODEL     = os.getenv('HERMES_WEBUI_DEFAULT_MODEL', 'openai/gpt-5.4-mini')
 
 # ── Startup diagnostics ───────────────────────────────────────────────────────
-def print_startup_config():
+def print_startup_config() -> None:
     """Print detected configuration at startup so the user can verify what was found."""
     ok   = '\033[32m[ok]\033[0m'
     warn = '\033[33m[!!]\033[0m'
@@ -243,7 +243,7 @@ def print_startup_config():
             flush=True
         )
 
-def verify_hermes_imports():
+def verify_hermes_imports() -> tuple:
     """
     Attempt to import the key Hermes modules.
     Returns (ok: bool, missing: list[str], errors: dict[str, str]).
@@ -366,7 +366,7 @@ _PROVIDER_MODELS = {
 }
 
 
-def resolve_model_provider(model_id: str):
+def resolve_model_provider(model_id: str) -> tuple:
     """Resolve bare model name, provider, and base_url for AIAgent.
 
     Model IDs from the dropdown may include a provider prefix
@@ -426,7 +426,9 @@ def get_available_models() -> dict:
     groups = []
 
     # 1. Read config.yaml model section
+    cfg_base_url = ''  # must be defined before conditional blocks (#117)
     model_cfg = cfg.get('model', {})
+    cfg_base_url = ''
     if isinstance(model_cfg, str):
         default_model = model_cfg
     elif isinstance(model_cfg, dict):
@@ -606,6 +608,25 @@ def get_available_models() -> dict:
         for provider_name, models in by_provider.items():
             groups.append({'provider': provider_name, 'models': models})
 
+    # Ensure the user's configured default_model always appears in the dropdown.
+    # It may be missing if the model isn't in any hardcoded list (e.g. openrouter/free,
+    # a custom local model, or any model.default not in _FALLBACK_MODELS).
+    if default_model:
+        all_ids = {m['id'] for g in groups for m in g.get('models', [])}
+        if default_model not in all_ids:
+            # Determine which group to inject into
+            label = default_model.split('/')[-1] if '/' in default_model else default_model
+            injected = False
+            for g in groups:
+                if active_provider and active_provider.lower() in g.get('provider', '').lower():
+                    g['models'].insert(0, {'id': default_model, 'label': label})
+                    injected = True
+                    break
+            if not injected and groups:
+                groups[0]['models'].insert(0, {'id': default_model, 'label': label})
+            elif not groups:
+                groups.append({'provider': active_provider or 'Default', 'models': [{'id': default_model, 'label': label}]})
+
     return {
         'active_provider': active_provider,
         'default_model': default_model,
@@ -653,6 +674,7 @@ _SETTINGS_DEFAULTS = {
     'show_token_usage': False,  # show input/output token badge below assistant messages
     'show_cli_sessions': False,  # merge CLI sessions from state.db into the sidebar
     'sync_to_insights': False,  # mirror WebUI token usage to state.db for /insights
+    'check_for_updates': True,  # check if webui/agent repos are behind upstream
     'theme': 'dark',  # active UI theme name (no enum gate -- allows custom themes)
     'password_hash': None,  # SHA-256 hash; None = auth disabled
 }
@@ -673,7 +695,7 @@ _SETTINGS_ALLOWED_KEYS = set(_SETTINGS_DEFAULTS.keys()) - {'password_hash'}
 _SETTINGS_ENUM_VALUES = {
     'send_key': {'enter', 'ctrl+enter'},
 }
-_SETTINGS_BOOL_KEYS = {'show_token_usage', 'show_cli_sessions', 'sync_to_insights'}
+_SETTINGS_BOOL_KEYS = {'show_token_usage', 'show_cli_sessions', 'sync_to_insights', 'check_for_updates'}
 
 def save_settings(settings: dict) -> dict:
     """Save settings to disk. Returns the merged settings. Ignores unknown keys."""

api/helpers.py

@@ -6,14 +6,14 @@ from pathlib import Path
 from api.config import IMAGE_EXTS, MD_EXTS
 
 
-def require(body: dict, *fields):
+def require(body: dict, *fields) -> None:
     """Phase D: Validate required fields. Raises ValueError with clean message."""
     missing = [f for f in fields if not body.get(f) and body.get(f) != 0]
     if missing:
         raise ValueError(f"Missing required field(s): {', '.join(missing)}")
 
 
-def bad(handler, msg, status=400):
+def bad(handler, msg, status: int=400):
     """Return a clean JSON error response."""
     return j(handler, {'error': msg}, status=status)
 
@@ -32,7 +32,7 @@ def _security_headers(handler):
     handler.send_header('Referrer-Policy', 'same-origin')
 
 
-def j(handler, payload, status=200):
+def j(handler, payload, status: int=200) -> None:
     """Send a JSON response."""
     body = _json.dumps(payload, ensure_ascii=False, indent=2).encode('utf-8')
     handler.send_response(status)
@@ -44,7 +44,7 @@ def j(handler, payload, status=200):
     handler.wfile.write(body)
 
 
-def t(handler, payload, status=200, content_type='text/plain; charset=utf-8'):
+def t(handler, payload, status: int=200, content_type: str='text/plain; charset=utf-8') -> None:
     """Send a plain text or HTML response."""
     body = payload if isinstance(payload, bytes) else str(payload).encode('utf-8')
     handler.send_response(status)
@@ -59,7 +59,7 @@ def t(handler, payload, status=200, content_type='text/plain; charset=utf-8'):
 MAX_BODY_BYTES = 20 * 1024 * 1024  # 20MB limit for non-upload POST bodies
 
 
-def read_body(handler):
+def read_body(handler) -> dict:
     """Read and JSON-parse a POST request body (capped at 20MB)."""
     length = int(handler.headers.get('Content-Length', 0))
     if length > MAX_BODY_BYTES:

api/models.py

@@ -34,12 +34,12 @@ def _write_session_index():
 
 
 class Session:
-    def __init__(self, session_id=None, title='Untitled',
+    def __init__(self, session_id: str=None, title: str='Untitled',
                  workspace=str(DEFAULT_WORKSPACE), model=DEFAULT_MODEL,
                  messages=None, created_at=None, updated_at=None,
-                 tool_calls=None, pinned=False, archived=False,
-                 project_id=None, profile=None,
-                 input_tokens=0, output_tokens=0, estimated_cost=None,
+                 tool_calls=None, pinned: bool=False, archived: bool=False,
+                 project_id: str=None, profile=None,
+                 input_tokens: int=0, output_tokens: int=0, estimated_cost=None,
                  **kwargs):
         self.session_id = session_id or uuid.uuid4().hex[:12]
         self.title = title
@@ -61,7 +61,7 @@ class Session:
     def path(self):
         return SESSION_DIR / f'{self.session_id}.json'
 
-    def save(self):
+    def save(self) -> None:
         self.updated_at = time.time()
         self.path.write_text(
             json.dumps(self.__dict__, ensure_ascii=False, indent=2),
@@ -76,7 +76,7 @@ class Session:
             return None
         return cls(**json.loads(p.read_text(encoding='utf-8')))
 
-    def compact(self):
+    def compact(self) -> dict:
         return {
             'session_id': self.session_id,
             'title': self.title,
@@ -165,7 +165,7 @@ def all_sessions():
     return result
 
 
-def title_from(messages, fallback='Untitled'):
+def title_from(messages, fallback: str='Untitled'):
     """Derive a session title from the first user message."""
     for m in messages:
         if m.get('role') == 'user':
@@ -180,7 +180,7 @@ def title_from(messages, fallback='Untitled'):
 
 # ── Project helpers ──────────────────────────────────────────────────────────
 
-def load_projects():
+def load_projects() -> list:
     """Load project list from disk. Returns list of project dicts."""
     if not PROJECTS_FILE.exists():
         return []
@@ -189,12 +189,12 @@ def load_projects():
     except Exception:
         return []
 
-def save_projects(projects):
+def save_projects(projects) -> None:
     """Write project list to disk."""
     PROJECTS_FILE.write_text(json.dumps(projects, ensure_ascii=False, indent=2), encoding='utf-8')
 
 
-def import_cli_session(session_id, title, messages, model='unknown', profile=None):
+def import_cli_session(session_id: str, title: str, messages, model: str='unknown', profile=None):
     """Create a new WebUI session populated with CLI messages.
     Returns the Session object.
     """
@@ -212,7 +212,7 @@ def import_cli_session(session_id, title, messages, model='unknown', profile=Non
 
 # ── CLI session bridge ──────────────────────────────────────────────────────
 
-def get_cli_sessions():
+def get_cli_sessions() -> list:
     """Read CLI sessions from the agent's SQLite store and return them as
     dicts in a format the WebUI sidebar can render alongside local sessions.
 
@@ -296,7 +296,7 @@ def get_cli_sessions():
     return cli_sessions
 
 
-def get_cli_session_messages(sid):
+def get_cli_session_messages(sid) -> list:
     """Read messages for a single CLI session from the SQLite store.
     Returns a list of {role, content, timestamp} dicts.
     Returns empty list on any error.
@@ -338,7 +338,7 @@ def get_cli_session_messages(sid):
     return msgs
 
 
-def delete_cli_session(sid):
+def delete_cli_session(sid) -> bool:
     """Delete a CLI session from state.db (messages + session row).
     Returns True if deleted, False if not found or error.
     """

api/profiles.py

@@ -137,7 +137,7 @@ def _reload_dotenv(home: Path):
         pass
 
 
-def init_profile_state():
+def init_profile_state() -> None:
     """Initialize profile state at server startup.
 
     Reads ~/.hermes/active_profile, sets HERMES_HOME env var, patches

api/routes.py

@@ -107,7 +107,7 @@ async function doLogin(e){
 
 # ── GET routes ────────────────────────────────────────────────────────────────
 
-def handle_get(handler, parsed):
+def handle_get(handler, parsed) -> bool:
     """Handle all GET routes. Returns True if handled, False for 404."""
 
     if parsed.path in ('/', '/index.html'):
@@ -227,6 +227,22 @@ def handle_get(handler, parsed):
         info = git_info_for_workspace(Path(s.workspace))
         return j(handler, {'git': info})
 
+    if parsed.path == '/api/updates/check':
+        settings = load_settings()
+        if not settings.get('check_for_updates', True):
+            return j(handler, {'disabled': True})
+        qs = parse_qs(parsed.query)
+        force = qs.get('force', ['0'])[0] == '1'
+        # ?simulate=1 returns fake behind counts for UI testing (localhost only)
+        if qs.get('simulate', ['0'])[0] == '1' and handler.client_address[0] == '127.0.0.1':
+            return j(handler, {
+                'webui': {'name': 'webui', 'behind': 3, 'current_sha': 'abc1234', 'latest_sha': 'def5678', 'branch': 'master'},
+                'agent': {'name': 'agent', 'behind': 1, 'current_sha': 'aaa0001', 'latest_sha': 'bbb0002', 'branch': 'master'},
+                'checked_at': 0,
+            })
+        from api.updates import check_for_updates
+        return j(handler, check_for_updates(force=force))
+
     if parsed.path == '/api/chat/stream/status':
         stream_id = parse_qs(parsed.query).get('stream_id', [''])[0]
         return j(handler, {'active': stream_id in STREAMS, 'stream_id': stream_id})
@@ -318,7 +334,7 @@ def handle_get(handler, parsed):
 
 # ── POST routes ───────────────────────────────────────────────────────────────
 
-def handle_post(handler, parsed):
+def handle_post(handler, parsed) -> bool:
     """Handle all POST routes. Returns True if handled, False for 404."""
 
     if parsed.path == '/api/upload':
@@ -600,6 +616,14 @@ def handle_post(handler, parsed):
     if parsed.path == '/api/session/import':
         return _handle_session_import(handler, body)
 
+    # ── Self-update (POST) ──
+    if parsed.path == '/api/updates/apply':
+        target = body.get('target', '')
+        if target not in ('webui', 'agent'):
+            return bad(handler, 'target must be "webui" or "agent"')
+        from api.updates import apply_update
+        return j(handler, apply_update(target))
+
     # ── CLI session import (POST) ──
     if parsed.path == '/api/session/import_cli':
         return _handle_session_import_cli(handler, body)

api/state_sync.py

@@ -43,7 +43,7 @@ def _get_state_db():
         return None
 
 
-def sync_session_start(session_id, model=None):
+def sync_session_start(session_id: str, model=None) -> None:
     """Register a WebUI session in state.db (idempotent).
     Called when a session's first message is sent.
     """
@@ -65,8 +65,8 @@ def sync_session_start(session_id, model=None):
             pass
 
 
-def sync_session_usage(session_id, input_tokens=0, output_tokens=0,
-                       estimated_cost=None, model=None, title=None):
+def sync_session_usage(session_id: str, input_tokens: int=0, output_tokens: int=0,
+                       estimated_cost=None, model=None, title: str=None) -> None:
     """Update token usage and title for a WebUI session in state.db.
     Called after each turn completes. Uses absolute=True to set totals
     (the WebUI Session already accumulates across turns).

api/streaming.py

@@ -17,6 +17,12 @@ from api.config import (
     resolve_model_provider,
 )
 
+# Global lock for os.environ writes. Per-session locks (_agent_lock) prevent
+# concurrent runs of the SAME session, but two DIFFERENT sessions can still
+# interleave their os.environ writes. This global lock serializes the env
+# save/restore around the entire agent run.
+_ENV_LOCK = threading.Lock()
+
 # Lazy import to avoid circular deps -- hermes-agent is on sys.path via api/config.py
 try:
     from run_agent import AIAgent
@@ -101,7 +107,7 @@ def _run_agent_streaming(session_id, msg_text, model, workspace, stream_id, atta
             HERMES_HOME=_profile_home,
         )
         # Still set process-level env as fallback for tools that bypass thread-local
-        with _agent_lock:
+        with _ENV_LOCK:
           old_cwd = os.environ.get('TERMINAL_CWD')
           old_exec_ask = os.environ.get('HERMES_EXEC_ASK')
           old_session_key = os.environ.get('HERMES_SESSION_KEY')

api/updates.py

@@ -0,0 +1,164 @@
+"""
+Hermes Web UI -- Self-update checker.
+
+Checks if the webui and hermes-agent git repos are behind their upstream
+branches. Results are cached server-side (30-min TTL) so git fetch runs
+at most twice per hour regardless of client count.
+
+Skips repos that are not git checkouts (e.g. Docker baked images where
+.git does not exist).
+"""
+import subprocess
+import threading
+import time
+from pathlib import Path
+
+from api.config import REPO_ROOT
+
+# Lazy -- may be None if agent not found
+try:
+    from api.config import _AGENT_DIR
+except ImportError:
+    _AGENT_DIR = None
+
+_update_cache = {'webui': None, 'agent': None, 'checked_at': 0}
+_cache_lock = threading.Lock()
+_check_in_progress = False
+_apply_lock = threading.Lock()   # prevents concurrent stash/pull/pop on same repo
+CACHE_TTL = 1800  # 30 minutes
+
+
+def _run_git(args, cwd, timeout=10):
+    """Run a git command and return (stdout, ok)."""
+    try:
+        r = subprocess.run(
+            ['git'] + args, cwd=str(cwd), capture_output=True,
+            text=True, timeout=timeout,
+        )
+        return r.stdout.strip(), r.returncode == 0
+    except (subprocess.TimeoutExpired, FileNotFoundError, OSError):
+        return '', False
+
+
+def _detect_default_branch(path):
+    """Detect the remote default branch (master or main)."""
+    out, ok = _run_git(['symbolic-ref', 'refs/remotes/origin/HEAD'], path)
+    if ok and out:
+        # refs/remotes/origin/master -> master
+        return out.split('/')[-1]
+    # Fallback: try master, then main
+    for branch in ('master', 'main'):
+        _, ok = _run_git(['rev-parse', '--verify', f'origin/{branch}'], path)
+        if ok:
+            return branch
+    return 'master'
+
+
+def _check_repo(path, name):
+    """Check if a git repo is behind its upstream. Returns dict or None."""
+    if path is None or not (path / '.git').exists():
+        return None
+
+    # Fetch latest from origin (network call, cached by TTL)
+    _, fetch_ok = _run_git(['fetch', 'origin', '--quiet'], path, timeout=15)
+    if not fetch_ok:
+        return {'name': name, 'behind': 0, 'error': 'fetch failed'}
+
+    branch = _detect_default_branch(path)
+
+    # Count commits behind
+    out, ok = _run_git(['rev-list', '--count', f'HEAD..origin/{branch}'], path)
+    behind = int(out) if ok and out.isdigit() else 0
+
+    # Get short SHAs for display
+    current, _ = _run_git(['rev-parse', '--short', 'HEAD'], path)
+    latest, _ = _run_git(['rev-parse', '--short', f'origin/{branch}'], path)
+
+    return {
+        'name': name,
+        'behind': behind,
+        'current_sha': current,
+        'latest_sha': latest,
+        'branch': branch,
+    }
+
+
+def check_for_updates(force=False):
+    """Return cached update status for webui and agent repos."""
+    global _check_in_progress
+    with _cache_lock:
+        if not force and time.time() - _update_cache['checked_at'] < CACHE_TTL:
+            return dict(_update_cache)
+        if _check_in_progress:
+            return dict(_update_cache)  # another thread is already checking
+        _check_in_progress = True
+
+    try:
+        # Run checks outside the lock (network I/O)
+        webui_info = _check_repo(REPO_ROOT, 'webui')
+        agent_info = _check_repo(_AGENT_DIR, 'agent')
+
+        with _cache_lock:
+            _update_cache['webui'] = webui_info
+            _update_cache['agent'] = agent_info
+            _update_cache['checked_at'] = time.time()
+            return dict(_update_cache)
+    finally:
+        _check_in_progress = False
+
+
+def apply_update(target):
+    """Stash, pull --ff-only, pop for the given target repo."""
+    if not _apply_lock.acquire(blocking=False):
+        return {'ok': False, 'message': 'Update already in progress'}
+    try:
+        return _apply_update_inner(target)
+    finally:
+        _apply_lock.release()
+
+
+def _apply_update_inner(target):
+    """Inner implementation of apply_update, called under _apply_lock."""
+    if target == 'webui':
+        path = REPO_ROOT
+    elif target == 'agent':
+        path = _AGENT_DIR
+    else:
+        return {'ok': False, 'message': f'Unknown target: {target}'}
+
+    if path is None or not (path / '.git').exists():
+        return {'ok': False, 'message': 'Not a git repository'}
+
+    branch = _detect_default_branch(path)
+
+    # Check for dirty working tree
+    status_out, _ = _run_git(['status', '--porcelain'], path)
+    stashed = False
+    if status_out:
+        _, ok = _run_git(['stash'], path)
+        if not ok:
+            return {'ok': False, 'message': 'Failed to stash local changes'}
+        stashed = True
+
+    # Pull with ff-only (no merge commits)
+    pull_out, pull_ok = _run_git(['pull', '--ff-only', 'origin', branch], path, timeout=30)
+    if not pull_ok:
+        if stashed:
+            _run_git(['stash', 'pop'], path)
+        return {'ok': False, 'message': f'Pull failed: {pull_out[:200]}'}
+
+    # Pop stash if we stashed
+    if stashed:
+        _, pop_ok = _run_git(['stash', 'pop'], path)
+        if not pop_ok:
+            return {
+                'ok': False,
+                'message': 'Updated but stash pop failed -- manual merge needed',
+                'stash_conflict': True,
+            }
+
+    # Invalidate cache
+    with _cache_lock:
+        _update_cache['checked_at'] = 0
+
+    return {'ok': True, 'message': f'{target} updated successfully', 'target': target}

api/upload.py

@@ -11,7 +11,7 @@ from api.models import get_session
 from api.workspace import safe_resolve_ws
 
 
-def parse_multipart(rfile, content_type, content_length):
+def parse_multipart(rfile, content_type, content_length) -> tuple:
     import re as _re, email.parser as _ep
     m = _re.search(r'boundary=([^;\s]+)', content_type)
     if not m:
@@ -70,7 +70,11 @@ def handle_upload(handler):
             return j(handler, {'error': 'Session not found'}, status=404)
         workspace = Path(s.workspace)
         safe_name = _re.sub(r'[^\w.\-]', '_', Path(filename).name)[:200]
-        dest = workspace / safe_name
+        # Reject names that are purely dots (path traversal: ".." survives regex)
+        if not safe_name or safe_name.strip('.') == '':
+            return j(handler, {'error': 'Invalid filename'}, status=400)
+        # Verify the resolved path stays within the workspace
+        dest = safe_resolve_ws(workspace, safe_name)
         dest.write_bytes(file_bytes)
         return j(handler, {'filename': safe_name, 'path': str(dest), 'size': dest.stat().st_size})
     except Exception as e:

api/workspace.py

@@ -176,7 +176,7 @@ def load_workspaces() -> list:
     return [{'path': _profile_default_workspace(), 'name': 'Home'}]
 
 
-def save_workspaces(workspaces: list):
+def save_workspaces(workspaces: list) -> None:
     ws_file = _workspaces_file()
     ws_file.parent.mkdir(parents=True, exist_ok=True)
     ws_file.write_text(json.dumps(workspaces, ensure_ascii=False, indent=2), encoding='utf-8')
@@ -202,7 +202,7 @@ def get_last_workspace() -> str:
     return _profile_default_workspace()
 
 
-def set_last_workspace(path: str):
+def set_last_workspace(path: str) -> None:
     try:
         lw_file = _last_workspace_file()
         lw_file.parent.mkdir(parents=True, exist_ok=True)
@@ -218,7 +218,7 @@ def safe_resolve_ws(root: Path, requested: str) -> Path:
     return resolved
 
 
-def list_dir(workspace: Path, rel='.'):
+def list_dir(workspace: Path, rel: str='.'):
     target = safe_resolve_ws(workspace, rel)
     if not target.is_dir():
         raise FileNotFoundError(f"Not a directory: {rel}")
@@ -235,7 +235,7 @@ def list_dir(workspace: Path, rel='.'):
     return entries
 
 
-def read_file_content(workspace: Path, rel: str):
+def read_file_content(workspace: Path, rel: str) -> dict:
     target = safe_resolve_ws(workspace, rel)
     if not target.is_file():
         raise FileNotFoundError(f"Not a file: {rel}")

server.py

@@ -18,7 +18,7 @@ class Handler(BaseHTTPRequestHandler):
     server_version = 'HermesWebUI/0.2'
     def log_message(self, fmt, *args): pass  # suppress default Apache-style log
 
-    def log_request(self, code='-', size='-'):
+    def log_request(self, code: str='-', size: str='-') -> None:
         """Structured JSON logs for each request."""
         import json as _json
         duration_ms = round((time.time() - getattr(self, '_req_t0', time.time())) * 1000, 1)
@@ -31,7 +31,7 @@ class Handler(BaseHTTPRequestHandler):
         })
         print(f'[webui] {record}', flush=True)
 
-    def do_GET(self):
+    def do_GET(self) -> None:
         self._req_t0 = time.time()
         try:
             parsed = urlparse(self.path)
@@ -43,7 +43,7 @@ class Handler(BaseHTTPRequestHandler):
             print(f'[webui] ERROR {self.command} {self.path}\n' + traceback.format_exc(), flush=True)
             return j(self, {'error': 'Internal server error'}, status=500)
 
-    def do_POST(self):
+    def do_POST(self) -> None:
         self._req_t0 = time.time()
         try:
             parsed = urlparse(self.path)
@@ -56,7 +56,7 @@ class Handler(BaseHTTPRequestHandler):
             return j(self, {'error': 'Internal server error'}, status=500)
 
 
-def main():
+def main() -> None:
     from api.config import print_startup_config, verify_hermes_imports, _HERMES_FOUND
 
     print_startup_config()

static/boot.js

@@ -308,7 +308,15 @@ document.querySelectorAll('.suggestion').forEach(btn=>{
 
 (async()=>{
   // Load send key preference
-  try{const s=await api('/api/settings');window._sendKey=s.send_key||'enter';window._showTokenUsage=!!s.show_token_usage;window._showCliSessions=!!s.show_cli_sessions;const _theme=s.theme||'dark';document.documentElement.dataset.theme=_theme;localStorage.setItem('hermes-theme',_theme);}catch(e){window._sendKey='enter';window._showTokenUsage=false;window._showCliSessions=false;}
+  let _bootSettings={};
+  try{const s=await api('/api/settings');_bootSettings=s;window._sendKey=s.send_key||'enter';window._showTokenUsage=!!s.show_token_usage;window._showCliSessions=!!s.show_cli_sessions;const _theme=s.theme||'dark';document.documentElement.dataset.theme=_theme;localStorage.setItem('hermes-theme',_theme);}catch(e){window._sendKey='enter';window._showTokenUsage=false;window._showCliSessions=false;_bootSettings={check_for_updates:false};}
+  // Non-blocking update check (fire-and-forget, once per tab session)
+  // ?test_updates=1 in URL forces banner display for testing (bypasses sessionStorage guards)
+  const _testUpdates=new URLSearchParams(location.search).get('test_updates')==='1';
+  if(_testUpdates||(_bootSettings.check_for_updates!==false&&!sessionStorage.getItem('hermes-update-checked')&&!sessionStorage.getItem('hermes-update-dismissed'))){
+    const _checkUrl='/api/updates/check'+(_testUpdates?'?simulate=1':'');
+    api(_checkUrl).then(d=>{if(!_testUpdates)sessionStorage.setItem('hermes-update-checked','1');if((d.webui&&d.webui.behind>0)||(d.agent&&d.agent.behind>0))_showUpdateBanner(d);}).catch(()=>{});
+  }
   // Fetch active profile
   try{const p=await api('/api/profile/active');S.activeProfile=p.name||'default';}catch(e){S.activeProfile='default';}
   // Update profile chip label immediately

static/index.html

@@ -14,7 +14,7 @@
 <body>
 <div class="layout">
   <aside class="sidebar">
-    <div class="sidebar-header"><div class="logo">H</div><div><h1 style="margin:0;font-size:15px;font-weight:700;letter-spacing:-.01em">Hermes</h1><div style="font-size:10px;color:var(--muted);opacity:.8;margin-top:1px">v0.34.3</div></div></div>
+    <div class="sidebar-header"><div class="logo">H</div><div><h1 style="margin:0;font-size:15px;font-weight:700;letter-spacing:-.01em">Hermes</h1><div style="font-size:10px;color:var(--muted);opacity:.8;margin-top:1px">v0.36</div></div></div>
     <div class="sidebar-nav">
       <button class="nav-tab active" data-panel="chat" data-label="Chat" onclick="switchPanel('chat')" title="Chat">&#128172;</button>
       <button class="nav-tab" data-panel="tasks" data-label="Tasks" onclick="switchPanel('tasks')" title="Tasks">&#128197;</button>
@@ -203,6 +203,13 @@
       <div class="messages-inner" id="msgInner"></div>
       <div id="liveToolCards" style="display:none;max-width:800px;margin:0 auto;width:100%;padding:0 24px;"></div>
     </div>
+    <div class="update-banner" id="updateBanner">
+      <span id="updateMsg"></span>
+      <div style="display:flex;gap:8px;flex-shrink:0">
+        <button class="update-btn" onclick="dismissUpdate()">Later</button>
+        <button class="update-btn update-primary" id="btnApplyUpdate" onclick="applyUpdates()">Update Now</button>
+      </div>
+    </div>
     <div class="reconnect-banner" id="reconnectBanner">
       <span id="reconnectMsg">&#9888; A response may have been in progress when you last left. Reload messages?</span>
       <div style="display:flex;gap:8px;flex-shrink:0">
@@ -319,10 +326,6 @@
         <label for="settingsModel">Default Model</label>
         <select id="settingsModel" style="width:100%;padding:8px;background:var(--code-bg);color:var(--text);border:1px solid var(--border2);border-radius:6px"></select>
       </div>
-      <div class="settings-field">
-        <label for="settingsWorkspace">Default Workspace</label>
-        <select id="settingsWorkspace" style="width:100%;padding:8px;background:var(--code-bg);color:var(--text);border:1px solid var(--border2);border-radius:6px"></select>
-      </div>
       <div class="settings-field">
         <label for="settingsSendKey">Send Key</label>
         <select id="settingsSendKey" style="width:100%;padding:8px;background:var(--code-bg);color:var(--text);border:1px solid var(--border2);border-radius:6px">
@@ -362,6 +365,13 @@
         </label>
         <div style="font-size:11px;color:var(--muted);margin-top:4px">Mirrors WebUI token usage to state.db so <code>hermes /insights</code> includes browser session data. Off by default.</div>
       </div>
+      <div class="settings-field">
+        <label style="display:flex;align-items:center;gap:8px;cursor:pointer">
+          <input type="checkbox" id="settingsCheckUpdates" style="width:15px;height:15px;accent-color:var(--accent)">
+          Check for updates
+        </label>
+        <div style="font-size:11px;color:var(--muted);margin-top:4px">Show a banner when newer versions of the WebUI or Agent are available. Runs a background git fetch periodically.</div>
+      </div>
       <div class="settings-field" style="border-top:1px solid var(--border);padding-top:12px;margin-top:8px">
         <label for="settingsPassword">Access Password</label>
         <div style="font-size:11px;color:var(--muted);margin-bottom:6px">Enter a new password to set or change it. Leave blank to keep current setting.</div>

static/panels.js

@@ -995,21 +995,6 @@ async function loadSettingsPanel(){
       modelSel.value=settings.default_model||'';
       modelSel.addEventListener('change',_markSettingsDirty,{once:false});
     }
-    // Populate workspace dropdown from /api/workspaces
-    const wsSel=$('settingsWorkspace');
-    if(wsSel){
-      wsSel.innerHTML='';
-      try{
-        const wsData=await api('/api/workspaces');
-        for(const w of (wsData.workspaces||[])){
-          const opt=document.createElement('option');
-          opt.value=w.path;opt.textContent=w.name||w.path;
-          wsSel.appendChild(opt);
-        }
-      }catch(e){}
-      wsSel.value=settings.default_workspace||'';
-      wsSel.addEventListener('change',_markSettingsDirty,{once:false});
-    }
     // Send key preference
     const sendKeySel=$('settingsSendKey');
     if(sendKeySel){sendKeySel.value=settings.send_key||'enter';sendKeySel.addEventListener('change',_markSettingsDirty,{once:false});}
@@ -1022,6 +1007,8 @@ async function loadSettingsPanel(){
     if(showCliCb){showCliCb.checked=!!settings.show_cli_sessions;showCliCb.addEventListener('change',_markSettingsDirty,{once:false});}
     const syncCb=$('settingsSyncInsights');
     if(syncCb){syncCb.checked=!!settings.sync_to_insights;syncCb.addEventListener('change',_markSettingsDirty,{once:false});}
+    const updateCb=$('settingsCheckUpdates');
+    if(updateCb){updateCb.checked=settings.check_for_updates!==false;updateCb.addEventListener('change',_markSettingsDirty,{once:false});}
     // Password field: always blank (we don't send hash back)
     const pwField=$('settingsPassword');
     if(pwField){pwField.value='';pwField.addEventListener('input',_markSettingsDirty,{once:false});}
@@ -1041,7 +1028,6 @@ async function loadSettingsPanel(){
 
 async function saveSettings(andClose){
   const model=($('settingsModel')||{}).value;
-  const workspace=($('settingsWorkspace')||{}).value;
   const sendKey=($('settingsSendKey')||{}).value;
   const showTokenUsage=!!($('settingsShowTokenUsage')||{}).checked;
   const showCliSessions=!!($('settingsShowCliSessions')||{}).checked;
@@ -1049,12 +1035,13 @@ async function saveSettings(andClose){
   const theme=($('settingsTheme')||{}).value||'dark';
   const body={};
   if(model) body.default_model=model;
-  if(workspace) body.default_workspace=workspace;
+
   if(sendKey) body.send_key=sendKey;
   body.theme=theme;
   body.show_token_usage=showTokenUsage;
   body.show_cli_sessions=showCliSessions;
   body.sync_to_insights=!!($('settingsSyncInsights')||{}).checked;
+  body.check_for_updates=!!($('settingsCheckUpdates')||{}).checked;
   // Password: only act if the field has content; blank = leave auth unchanged
   if(pw && pw.trim()){
     try{

static/style.css

@@ -145,6 +145,13 @@
   .reconnect-banner.visible{display:flex;}
   .reconnect-btn{padding:5px 12px;border-radius:7px;font-size:12px;font-weight:600;background:rgba(201,168,76,0.15);border:1px solid rgba(201,168,76,0.4);color:var(--gold);cursor:pointer;}
   .reconnect-btn:hover{background:rgba(201,168,76,0.25);}
+  /* ── Update banner ── */
+  .update-banner{display:none;background:var(--surface);border:1px solid rgba(124,185,255,0.4);border-radius:10px;padding:10px 16px;margin:10px auto;max-width:780px;font-size:13px;color:var(--blue);align-items:center;justify-content:space-between;gap:12px;}
+  .update-banner.visible{display:flex;}
+  .update-btn{padding:5px 12px;border-radius:7px;font-size:12px;font-weight:600;background:rgba(124,185,255,0.1);border:1px solid rgba(124,185,255,0.3);color:var(--blue);cursor:pointer;transition:background .15s;}
+  .update-btn:hover{background:rgba(124,185,255,0.2);}
+  .update-primary{background:rgba(124,185,255,0.2);border-color:rgba(124,185,255,0.5);}
+  .update-btn:disabled{opacity:0.5;cursor:not-allowed;}
   /* ── Approval card ── */
   .approval-card{display:none;max-width:780px;margin:0 auto 0;padding:0 20px 12px;}
   .approval-card.visible{display:block;}

static/ui.js

@@ -334,6 +334,47 @@ async function refreshSession() {
     showToast('Conversation refreshed');
   } catch(e) { setStatus('Refresh failed: ' + e.message); }
 }
+// ── Update banner ──
+function _showUpdateBanner(data){
+  const parts=[];
+  if(data.webui&&data.webui.behind>0) parts.push(`WebUI: ${data.webui.behind} update${data.webui.behind>1?'s':''}`);
+  if(data.agent&&data.agent.behind>0) parts.push(`Agent: ${data.agent.behind} update${data.agent.behind>1?'s':''}`);
+  if(!parts.length)return;
+  const msg=$('updateMsg');
+  if(msg) msg.textContent='\u2B06 '+parts.join(', ')+' available';
+  const banner=$('updateBanner');
+  if(banner) banner.classList.add('visible');
+  window._updateData=data;
+}
+function dismissUpdate(){
+  const b=$('updateBanner');if(b)b.classList.remove('visible');
+  sessionStorage.setItem('hermes-update-dismissed','1');
+}
+async function applyUpdates(){
+  const btn=$('btnApplyUpdate');
+  if(btn){btn.disabled=true;btn.textContent='Updating\u2026';}
+  const targets=[];
+  if(window._updateData?.webui?.behind>0) targets.push('webui');
+  if(window._updateData?.agent?.behind>0) targets.push('agent');
+  try{
+    for(const target of targets){
+      const res=await api('/api/updates/apply',{method:'POST',body:JSON.stringify({target})});
+      if(!res.ok){
+        showToast('Update failed ('+target+'): '+(res.message||'unknown error'));
+        if(btn){btn.disabled=false;btn.textContent='Update Now';}
+        return;
+      }
+    }
+    showToast('Updated! Reloading\u2026');
+    sessionStorage.removeItem('hermes-update-checked');
+    sessionStorage.removeItem('hermes-update-dismissed');
+    setTimeout(()=>location.reload(),1500);
+  }catch(e){
+    showToast('Update failed: '+e.message);
+    if(btn){btn.disabled=false;btn.textContent='Update Now';}
+  }
+}
+
 async function checkInflightOnBoot(sid) {
   const raw = localStorage.getItem(INFLIGHT_KEY);
   if (!raw) return;