feat: migrate daily-brief implementation notes

knowledge-base/automation-blueprints/hermes/notes/daily-brief-implementation.md

@@ -0,0 +1,54 @@
+# Daily Brief — Implementation Notes
+
+## Architecture: context-from Chaining
+
+```
+┌──────────────────────────────┐
+│  cron: 0 15 * * *            │
+│  script: collector.sh        │  ← no-agent, free public APIs
+├──────────────────────────────┤
+│  Script stdout → agent       │  ← injected as prompt context
+│  context                     │
+├──────────────────────────────┤
+│  Agent: curates → formats    │  ← lightweight LLM pass only
+│  → delivers to Telegram      │
+└──────────────────────────────┘
+```
+
+## Cost Breakdown
+
+| Stage | Token Cost | Frequency |
+|-------|-----------|-----------|
+| Script fetch (shell) | $0 | 1x per tick |
+| Agent curation | Full model | 1x per tick |
+
+vs. old approach that relied on web_search + x_search (both failing silently).
+
+## Sources (Free, No API Key)
+
+| Source | Endpoint | Reliability |
+|--------|----------|-------------|
+| Weather | `wttr.in/Placerville,CA` | 99.9% |
+| Hacker News | Firebase API (v0) | 99.9% |
+| GitHub Trending | `api.github.com/search/repositories` | 99% (unauthed rate limit: 60/hr) |
+
+## Previous State (Before June 20)
+
+Old prompt instructed the agent to use web_search and x_search tools. Both were failing — Firecrawl unconfigured, xAI credits exhausted. Brief returned `[SILENT]` for weeks.
+
+## Key Insight
+
+The script + context_from pattern turned a dead cron job into a working one in <5 minutes with zero ongoing API costs.
+
+## Cron Job (Production)
+
+```bash
+hermes cron update e94447937052 \
+  --script daily-brief-collector.sh \
+  --prompt "Curate from the injected context. Output max 8 bullets. Silent if no data."
+```
+
+- **Job ID:** e94447937052
+- **Schedule:** `0 15 * * *` (3pm UTC = 8am PDT)
+- **Delivery:** Telegram (here)
+- **Model:** grok-4.3 via xai-oauth