Second Brain — Project Repo

Planning workspace for an AI second-brain / live journaling + synthesis app.

Positioning: Strategist (lead), architected for Mirror and Chief of Staff. Jurisdiction: US-based operation. Current phase: pre-Phase-0. Docs complete; ready to build.

Structure

second-brain/
├── README.md                        ← index, decisions, next actions
├── CLAUDE-CODE-PROMPT.md            ← paste this into Claude Code to start building
└── docs/
    ├── 01-product-brief.md          ← original brainstorm: thesis, architecture, competitors, cost model
    ├── 02-solo-v1-plan.md           ← rev.2: phases, privacy decision, US legal, cheap stack
    ├── 03-engine-spec.md            ← THE PRODUCT: four horizons, scoring, anti-generic contract
    ├── 04-onboarding-and-retention.md ← cold start, return-trigger psychology, distribution
    └── 05-corpus-bootstrap.md        ← getting data in: AI exports, handwriting, MCP, local-Docker notes

Read order for anyone new: 01 → 03 → 05 → 02 → 04.

To add later: 05-crisis-detection.md (prerequisite for any Mirror positioning), 06-competitive-teardowns.md, evals/ (the regression set).

Decision log

Date	Decision	Rationale	Status
2026-08-12	Do not build on Obsidian; do adopt its format	App is proprietary — ToS bars redistribution, derivative works, competing products, and providing a service to others. The format (Markdown + YAML + [[wikilinks]]) is free and unlicensable	✅
2026-08-12	Markdown files are the format of record; Postgres is the index	Makes "no lock-in" verifiable, not just promised	✅
2026-08-12	Three positionings = one engine, horizon as a parameter	Same capture, atoms, graph. Only output framing differs	✅
2026-08-12	Lead with Strategist; Mirror after v1 pilot + crisis detection	Strategist's worst output is boring; Mirror's is harmful	✅
2026-08-13	Strategist runs on all four horizons, not just months	Value must arrive day one. Resonance pings fire instantly	✅ Revised
2026-08-13	Privacy: plaintext in Phase 0, encryption boundary from commit #1, envelope encryption before user #2	Crypto is cheap; encrypted columns break search and debugging. The single data-access module is what actually buys the option	✅ Revised
2026-08-13	US jurisdiction: MHMDA + FTC HBNR + FTC §5, no GDPR	Operation is US-based. MHMDA's private right of action is the main exposure	✅
2026-08-13	Backfill import is a Phase 0 feature, built before live capture	Solves cold start and the validation problem in one move	✅ Revised
2026-08-13	No streaks, no variable rewards, no guilt. Absence = accumulation	Streaks punish the people who need this most; the app maps vulnerabilities and must not exploit them	✅
2026-08-13	Publish the format spec as an open standard	Best organic distribution wedge; reaches the PKM/Obsidian audience	✅ Direction set
2026-08-13	Python 3.12 everywhere; FastAPI + Jinja + HTMX. Next.js deferred to Phase 2	Engine deps are Python-native with no good JS equivalent (faster-whisper, sentence-transformers, leidenalg, ruptures). Phase 0 UI is a form and a list	✅
2026-08-13	Fully local Docker for Phase 0; Tailscale for phone capture	$0, no cloud accounts, nothing publicly exposed	✅
2026-08-13	Catch-up jobs, never scheduled jobs	Laptop sleeps. Designing for intermittent availability is free now, miserable to retrofit	✅
2026-08-13	AI chat history: import via official export, not a live connector	No read API exists for ChatGPT or Claude history. Anything else is scraping	✅
2026-08-13	Expose the brain as an MCP server (capture / recall / resonance / open_loops)	The correct inversion of "connect to ChatGPT." Claude Desktop reaches local servers today; ChatGPT needs a remote one, so that half is Phase 2	✅
2026-08-13	Handwritten journal ingestion is a Phase 0 importer	It's the corpus that exists. Vision model → text + inferred original date	✅
—	Handwriting OCR: hosted (better) vs local (private)	Suggested default: hosted one-time batch under ZDR, everything ongoing local	⬜ Open — decide per batch
—	Free tier + pricing	Deferred to Phase 2	⬜ Open
—	EU users: take them or not?	Taking them re-imports GDPR + DPIA. Decide deliberately	⬜ Open

Next actions

1. Request your ChatGPT and Claude data exports today. Settings → Data controls → Export data. They take up to 24 hours and they are the highest-value input to Phase 0.
2. Photograph your handwritten journals while you wait. One page per image, even light, batched by notebook.
3. Paste CLAUDE-CODE-PROMPT.md into Claude Code. Review CLAUDE.md and the proposed schema before letting it build anything.
4. Judge the resonances before building synthesis. If step 5's retroactive resonances are boring, stop and fix retrieval. Don't build the weekly engine on a broken foundation.
5. Label everything into evals/ from the first output. The labelled set is the moat.
6. Set up backups before you have anything worth losing.

Hard constraints (do not violate)

• Never train on user data. Never sell it. Never use it for advertising. These are also the legal shield under FTC Act §5.
• Every insight cites the specific entries that produced it.
• Markdown export works from day one.
• No minors.
• No diagnosis, no treatment claims, no therapy branding.
• No dark patterns: no streaks, no variable-ratio rewards, no guilt, no engagement-optimised timing.
• Optimise for "was this true and useful," never for time-in-app.