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+# Deep Dive Architecture
+
+Technical specification for the automated daily intelligence briefing system.
+
+## System Overview
+
+```
+┌─────────────┬─────────────┬─────────────┬─────────────┬─────────────┐
+│   Phase 1   │   Phase 2   │   Phase 3   │   Phase 4   │   Phase 5   │
+│  Aggregate  │   Filter    │  Synthesize │    TTS      │   Deliver   │
+├─────────────┼─────────────┼─────────────┼─────────────┼─────────────┤
+│ arXiv RSS   │ Chroma DB   │ Claude/GPT  │   Piper     │  Telegram   │
+│ Lab Blogs   │ Embeddings  │   Prompt    │   (local)   │   Voice     │
+└─────────────┴─────────────┴─────────────┴─────────────┴─────────────┘
+```
+
+## Data Flow
+
+1. **Aggregation**: Fetch from arXiv + lab blogs
+2. **Relevance**: Score against Hermes context via embeddings
+3. **Synthesis**: LLM generates structured briefing
+4. **TTS**: Piper converts to audio (Opus)
+5. **Delivery**: Telegram voice message
+
+## Source Coverage
+
+| Source | Method | Frequency |
+|--------|--------|-----------|
+| arXiv cs.AI | RSS | Daily |
+| arXiv cs.CL | RSS | Daily |
+| arXiv cs.LG | RSS | Daily |
+| OpenAI Blog | RSS | Weekly |
+| Anthropic | RSS | Weekly |
+| DeepMind | Scraper | Weekly |
+
+## Relevance Scoring
+
+**Keyword Layer**: Match against 20+ Hermes keywords
+**Embedding Layer**: `all-MiniLM-L6-v2` + Chroma DB
+**Composite**: `0.3 * keyword_score + 0.7 * embedding_score`
+
+## TTS Pipeline
+
+- **Engine**: Piper (`en_US-lessac-medium`)
+- **Speed**: ~1.5x realtime on CPU
+- **Format**: WAV → FFmpeg → Opus (24kbps)
+- **Sovereign**: Fully local, zero API cost
+
+## Cron Integration
+
+```yaml
+job:
+  name: deep-dive-daily
+  schedule: "0 6 * * *"
+  command: python3 orchestrator.py --cron
+```
+
+## On-Demand
+
+```bash
+python3 orchestrator.py        # Full run
+python3 orchestrator.py --dry-run    # No delivery
+python3 orchestrator.py --skip-tts   # Text only
+```
+
+## Acceptance Criteria
+
+| Criterion | Status |
+|-----------|--------|
+| Zero manual copy-paste | ✅ Automated |
+| Daily 6 AM delivery | ✅ Cron ready |
+| arXiv + labs coverage | ✅ RSS + scraper |
+| Hermes relevance filter | ✅ Embeddings |
+| Written briefing | ✅ LLM synthesis |
+| Audio via TTS | ✅ Piper pipeline |
+| Telegram delivery | ✅ Voice API |
+| On-demand command | ✅ CLI flags |
+
+---
+**Epic**: #830 | **Status**: Architecture Complete