diff --git a/CLAUDE.md b/CLAUDE.md
new file mode 100644
index 0000000..2ff0752
--- /dev/null
+++ b/CLAUDE.md
@@ -0,0 +1,38 @@
+# T YouTube — Text-Based YouTube Digest
+
+## PDD Workflow
+
+This project follows **PDD (Product Definition Document)** development.
+
+**Always read these files before writing code:**
+- `docs/PDD.md` — product vision, goals, targets (the north star)
+- `docs/specs/active.md` — current sprint spec (what we're building now)
+
+**Workflow:**
+1. PDD → Sprint Spec → Implementation → Validate ACs
+2. Scope changes update the sprint spec first, code second
+3. Never ship without ACs passing
+
+## Dev Commands
+
+- **Build:** `docker compose up -d --build`
+- **Test:** `./run_tests.sh`
+- **Run locally:** `uvicorn backend.main:app --reload` (backend) + `npm run dev` (frontend)
+- **Sync subscriptions:** `python run_sync.py`
+
+## Architecture
+
+- **Frontend:** Svelte 5 + Vite (`frontend/`)
+- **Backend:** FastAPI + SQLite (`backend/`)
+- **Deployment:** Docker container on NAS DS224+, port 8001
+- **Sync:** `run_sync.py` fetches YouTube subscriptions + transcripts via yt-dlp
+- **Auth:** Authelia SSO in front, cookie-based session
+- **Proxy:** YouTube blocked from China — sync runs via VPS (Oracle Tokyo) or proxy
+
+## Key Files
+
+- `docs/architecture.md` — full architecture reference
+- `Dockerfile` — multi-stage build (node → python)
+- `docker-compose.yml` — deployment config
+- `run_sync.py` — subscription sync entry point
+- `config/cookies.txt` — YouTube auth cookies (not committed)
diff --git a/docs/PDD.md b/docs/PDD.md
new file mode 100644
index 0000000..d1629d8
--- /dev/null
+++ b/docs/PDD.md
@@ -0,0 +1,21 @@
+# Product Definition Document — T YouTube
+
+## Vision
+
+A text-first YouTube experience — read transcripts, get AI summaries, never watch a video.
+
+## Goals
+
+1. **No-video YouTube** — read subscriptions, watch content as text, never open the YouTube app
+2. **Daily digest** — AI-summarized subscription feed delivered to Telegram daily
+3. **GFW-proof** — works reliably from China despite YouTube blocks
+
+## Target Users
+
+Self (Jimmy Gan). Primary use: morning skim of YouTube subscriptions via text summaries.
+
+## Success Metrics
+
+- Daily sync completes without errors
+- Telegram digest delivered every morning
+- < 5s page load for dashboard
diff --git a/docs/configuration.md b/docs/configuration.md
new file mode 100644
index 0000000..8473ff5
--- /dev/null
+++ b/docs/configuration.md
@@ -0,0 +1,152 @@
+# t-youtube Configuration Guide
+
+## Environment Variables
+
+### Backend (.env)
+```bash
+# Database path
+DB_DIR=/volume1/docker/t-youtube/backend
+
+# API Token (for write operations)
+API_TOKEN=<your-api-token>
+
+# DeepSeek API (for summarization)
+DEEPSEEK_API_KEY=<your-key>
+
+# YouTube Data API v3
+GOOGLE_APPLICATION_CREDENTIALS=/path/to/credentials.json
+```
+
+### Docker Compose
+```yaml
+version: "3"
+services:
+  t-youtube:
+    build: .
+    ports:
+      - "8001:8001"
+    environment:
+      - DB_DIR=/backend/data
+      - API_TOKEN=<your-token>
+      - DEEPSEEK_API_KEY=<your-key>
+    volumes:
+      - ./backend/data:/backend/data
+```
+
+## API Token Management
+
+### Generation
+```bash
+python3 -c "import secrets; print('api-' + secrets.token_urlsafe(32))"
+```
+
+### Frontend Setup
+- First-time users see a token setup modal
+- Token stored in localStorage
+- Bearer token sent with all API write requests
+
+### Backend Validation
+- Middleware checks `Authorization: Bearer <token>` for POST/PATCH/DELETE on `/api/*`
+- Returns 401 JSON for invalid tokens
+- GET endpoints remain open to authenticated frontend users
+
+## Database Management
+
+### Location
+- **Path**: `/volume1/docker/t-youtube/backend/t_youtube.db`
+- **Type**: SQLite (aiosqlite)
+- **Backup**: Copy the `.db` file before any schema changes
+
+### Schema Migrations
+- Use `sqlite3` CLI or a migration script
+- Always add indexes after schema changes
+- Example:
+  ```bash
+  sqlite3 t_youtube.db "CREATE INDEX IF NOT EXISTS idx_x ON table(column);"
+  ```
+
+### Daily Sync Configuration
+
+#### Cron Job
+```bash
+# Runs every day at 3 AM
+0 3 * * * /path/to/run_sync.py >> /var/log/t-youtube-sync.log 2>&1
+```
+
+#### Fetcher Settings
+- **RSS**: Free, unlimited, ~2000 channels
+- **YouTube Data API v3**: ~50 units per sync
+- **Rotation**: Fetches in slices to avoid timeouts
+- **Retry**: Automatic retry on failure
+
+#### Summarizer Settings
+- **Model**: `deepseek-chat` via DeepSeek API
+- **Timeout**: 30 seconds per video
+- **Fallback**: Video description if transcript unavailable
+- **Language**: Follows content language (Chinese → Chinese summary)
+
+## Authelia Integration
+
+### Authentication Flow
+1. User accesses protected domain
+2. Caddy forwards request to Authelia (`127.0.0.1:9092`)
+3. Authelia checks session/2FA
+4. If no session → redirect to `auth.jimmygan.com`
+5. If session exists → return 200 (allowed)
+
+### 2FA Methods
+- **WebAuthn (Primary)**: Passkey via iCloud Keychain/Bitwarden
+- **TOTP (Fallback)**: Time-based one-time password
+
+### Configuration
+- **Address**: `127.0.0.1:9092`
+- **Database**: SQLite (`/volume1/docker/authelia/config/db.sqlite3`)
+- **LDAP Backend**: LLDAP (`lldap:3890`)
+- **Session**: 1 hour expiration, 5 minute inactivity timeout
+
+### Restart Authelia
+```bash
+cd /volume1/docker/authelia && /usr/local/bin/docker compose restart authelia
+```
+
+## Caddy Configuration
+
+### VPS Caddy (Public)
+- **Port**: 443
+- **TLS**: Let's Encrypt (HTTP-01)
+- **Authelia**: `forward_auth 100.78.131.124:9092`
+- **DNS**: dnsmasq → VPS Tailscale IP `100.109.198.126`
+
+### NAS Caddy (Local/Tailscale)
+- **Port**: 8443 (fallback due to SNI bug)
+- **TLS**: Cloudflare DNS-01
+- **Authelia**: `forward_auth 127.0.0.1:9092`
+- **SNI Bug**: Per-site `tls` blocks cause cert routing issues
+- **Workaround**: Global TLS config + dnsmasq → VPS Tailscale IP
+
+### Reloading Caddy
+```bash
+# VPS
+ssh caddy-vps "sudo systemctl reload caddy"
+
+# NAS
+cd /volume1/docker/caddy && /usr/local/bin/docker compose restart caddy
+```
+
+## Monitoring & Health
+
+### Health Check
+```bash
+curl -s https://yt.jimmygan.com/api/health
+# Expected: {"status": "ok"}
+```
+
+### Sync Status
+- Check `run_sync.py` logs in `/var/log/t-youtube-sync.log`
+- Monitor DB for new videos/summaries
+- Verify cron job is active: `crontab -l`
+
+### Database Size
+```bash
+ls -lh /volume1/docker/t-youtube/backend/t_youtube.db
+```
diff --git a/docs/progress.md b/docs/progress.md
new file mode 100644
index 0000000..52d4c25
--- /dev/null
+++ b/docs/progress.md
@@ -0,0 +1,102 @@
+# t-youtube Progress Tracking
+
+## Session 2026-07-09: Agent Queue, Notes Migration, Architecture Documentation
+
+### Completed
+- [x] **Agent Queue Feature**:
+  - Added `agent_queue` table to SQLite DB
+  - Implemented `POST/GET/DELETE` endpoints in `main.py`
+  - Created `agent_worker.py` skeleton for processing pending items
+  - Frontend "Agent Queue" tab (Svelte 5) with status indicators
+- [x] **Notes Migration**:
+  - Moved notes from localStorage to server-side DB (`video_notes` table)
+  - Added `POST/GET/DELETE` endpoints for notes
+  - Implemented non-blocking localStorage migration script
+- [x] **Database Optimization**:
+  - Added indexes on `video_id` for `agent_queue` and `video_notes` tables
+- [x] **Authelia Configuration**:
+  - Attempted passwordless mode (failed due to unsupported key in Authelia v4)
+  - Reverted to standard 2FA (WebAuthn/TOTP)
+- [x] **Documentation**:
+  - Created `docs/` folder with `architecture.md` and `progress.md`
+  - Documented all API endpoints, DB schema, infrastructure, and known issues
+
+### In Progress
+- [ ] **Agent Worker Logic**:
+  - `agent_worker.py` needs actual LLM/feature-creation logic
+  - Pending: Define workflow for processing queued items
+- [ ] **YouTube Sync Monitoring**:
+  - Daily cron at 3 AM is active
+  - Pending: Monitor next run for errors/progress
+
+### Planned
+- [ ] **Channel Categorization**:
+  - ~119 channels remain uncategorized
+  - Consider moving `AUTO_CATEGORIES` to server-side JSON config
+- [ ] **Transcript Fallback**:
+  - Implement browser-based scraping (playwright/selenium) for the remaining 10%
+  - High complexity/resource usage trade-off
+- [ ] **Performance Monitoring**:
+  - Add health check endpoints for sync status
+  - Implement error logging/reporting
+
+## Session 2026-07-05 to 2026-07-08: Initial Development
+
+### Key Milestones
+- [x] **YouTube Data API v3 + RSS Hybrid**: Replaced yt-dlp/cookies approach
+  - Free, unlimited sync (~50 units/sync for 200+ channels)
+  - 2414 new videos discovered in first run
+- [x] **AI Summarization**: DeepSeek API integration (was Claude/bytecatcode)
+  - Chinese content → Chinese summary; English content → English summary
+  - ~2.1s per video, ~$0.001 each
+- [x] **Frontend Overhaul**:
+  - AI Digest as hero element
+  - Keyboard navigation (`j/k/↑↓`, `r/m`, `s`, `n`, `Enter`, `?`)
+  - Dark/light mode toggle
+  - Channel filter dropdown with auto-generated categories
+  - Auto-read after 3s silent mark
+- [x] **Agent Queue Integration**:
+  - "Save to Agent" feature: notes ARE prompts for Hermes agents
+  - Queue tab with pending/processing/done status
+  - Cross-device note sync (localStorage → server DB)
+
+### Technical Decisions
+1. **API Token Auth**: Bearer token for API writes, Authelia SSO for frontend
+2. **SQLite**: Simple, reliable, no external dependencies for single-user setup
+3. **DeepSeek API**: Cost-effective for summarization (~$0.001/video)
+4. **Svelte 5**: Reactivity model, keyboard workflow, small bundle size
+5. **RSS + YouTube Data API**: Free tier sufficient, avoids cookie/yt-dlp maintenance
+
+## Session 2026-07-04: NAS & Authelia Setup
+
+### Completed
+- [x] NAS Caddy port 443 conflict resolved (DSM nginx)
+- [x] dnsmasq → VPS Caddy Tailscale IP (100.109.198.126)
+- [x] Authelia WebAuthn enabled, passkey registered
+- [x] TOTP reset for jimmy, default 2FA set to WebAuthn
+- [x] Caddy SNI bug workaround (global TLS config, port 8443 fallback)
+
+## Known Issues & Resolutions
+
+### Authelia Passwordless Failure
+- **Issue**: `webauthn.passwordless: true` caused boot loop (`configuration key not expected`)
+- **Root Cause**: Unsupported configuration key in current Authelia version
+- **Resolution**: Reverted to standard 2FA (WebAuthn/TOTP)
+
+### YouTube Transcript Blocking
+- **Issue**: 90% of videos have transcripts; 10% fail due to Oracle Cloud IP blocking
+- **Root Cause**: YouTube IP-based restrictions
+- **Resolution**: Fallback to video description summaries; consider browser-based scraping later
+
+### NAS Caddy SNI Bug
+- **Issue**: NAS Caddy serves first cached cert for all SNI names
+- **Root Cause**: Per-site `tls { ... }` blocks conflict with global auto_https policy
+- **Resolution**: Global TLS config + dnsmasq → VPS Caddy Tailscale IP
+
+## Metrics & Performance
+- **Videos in DB**: ~2414+ (initial sync)
+- **Channels**: ~229 subscribed
+- **Sync Time**: ~2-3 minutes for all channels
+- **Summarization**: ~2.1s/video, ~$0.001 each via DeepSeek
+- **Frontend Load Time**: 0.14-0.22s (API responses)
+- **Daily API Usage**: ~50 units (well within 10,000/day free tier)
diff --git a/docs/specs/active.md b/docs/specs/active.md
new file mode 120000
index 0000000..3a78b09
--- /dev/null
+++ b/docs/specs/active.md
@@ -0,0 +1 @@
+sprint-001-sync-reliability.md
\ No newline at end of file
diff --git a/docs/specs/sprint-001-sync-reliability.md b/docs/specs/sprint-001-sync-reliability.md
new file mode 100644
index 0000000..d7b2d52
--- /dev/null
+++ b/docs/specs/sprint-001-sync-reliability.md
@@ -0,0 +1,32 @@
+# Sprint 001 — Sync Reliability & Telegram Delivery
+
+**Dates:** Active
+
+## Goals
+
+- Fix daily sync on NAS
+- Verify Telegram delivery pipeline
+- Stabilize subscription fetching behind GFW
+
+## Tasks
+
+### T1: Fix daily sync cron
+
+**Description:**
+`t-youtube-daily-sync` errored last run. Determine if `run_sync.py` is the active pipeline or if VPS-based `fetch_and_sync.sh` replaced it. Fix whichever is active.
+
+**ACs:**
+- [ ] Daily sync completes without errors
+- [ ] New videos appear in dashboard
+
+**Impl Notes:**
+Check NAS cron logs. VPS sync fires every 6h.
+
+### T2: Verify tg-group-filter delivery
+
+**Description:**
+Cron switched from `deliver: local` to `deliver: all`. Confirm Telegram delivery works for filtered results.
+
+**ACs:**
+- [ ] Telegram receives filtered video digest
+- [ ] No duplicate deliveries