# Second Brain OS — Vault Reference This is the folder-by-folder reference guide. For setup, philosophy, and the AI briefing prompt, start with **START-HERE.md**. --- ## Vault structure ``` 00-Inbox/ — all new captures land here first 00-Memory/ — per-fact store (one fact = one file) 01-Projects/ — one folder per active project 03-Decisions/ — major decisions that span projects 04-Handoffs/ — session-ending summaries 05-Patterns/ — reusable formats and procedures 06-Lessons/ — things you've learned 07-Reviews/ — retrospectives and audits ``` --- ## 00-Inbox/ **What it is:** The landing zone for everything. Nothing gets classified here — it just lands. **What goes here:** Any new capture: an idea, a task, a link, a note from a conversation, a thing you need to do later. Everything without a clear home starts here. **How it works:** Every capture hits the inbox before it gets a permanent home. Triage on a regular cadence (daily or weekly) by moving each item to its proper location. **The rule that can't have exceptions:** When in doubt, inbox first. The exceptions are always where things get lost. --- ## 00-Memory/ **What it is:** The per-fact store. The part that makes AI sessions dramatically more efficient. **What goes here:** Facts about you — preferences, working style, technical decisions, standing constraints, recurring policies. One fact per file. **Naming:** Kebab-case, descriptive. `my-code-review-preferences.md`. `client-billing-cycle.md`. `current-tech-stack.md`. The filename IS the index. **File format:** ``` --- type: preference | reference | decision | constraint tags: [optional, keywords] updated: YYYY-MM-DD --- [The fact, written for an AI to read. 2-5 sentences. Context for when it applies. No prose padding.] ``` **How the AI uses it:** Tell your AI: "My memory store is in 00-Memory/. Grep by keyword when you need context." The AI searches the folder, reads the relevant files, and has context — without you re-explaining. **See also:** `00-Memory/example-*.md` files for worked examples of the format. --- ## 01-Projects/ **What it is:** One folder per active project. Each folder has exactly three files. **Folder naming:** kebab-case. `my-portfolio-site/`. `freelance-client-acme/`. `app-rewrite/`. **The three files every project gets:** `status.md` — current state. One page. What phase you're in, what's done, what's next, what's blocked. Written so someone (or an AI) can pick up in 60 seconds. `tasks.md` — three sections: `## Active`, `## Blocked`, `## Done`. Checkbox items. Nothing more complex. `decisions.md` — non-trivial calls and the reasoning behind them. Dated entries. Not a log of everything — just the calls you might question later. **The `_template/` subfolder** contains blank copies of all three files. Copy the whole `_template/` folder when starting a new project. **When a project is done:** Archive the folder to `07-Reviews/YYYY-MM-archive/[project-name]/` or simply mark status.md as complete and stop touching it. --- ## 03-Decisions/ **What it is:** A permanent log of significant decisions that apply across multiple projects or represent major directional choices. **What goes here:** Technology choices, product directions, business model decisions, anything you might want to audit in 6 months and understand "why did I do that?" **What doesn't go here:** Project-specific decisions (those go in `01-Projects/[name]/decisions.md`). Routine task calls. Preferences (those go in `00-Memory/`). **File naming:** `YYYY-MM-DD-kebab-topic.md` **File format:** See `03-Decisions/_schema.md`. --- ## 04-Handoffs/ **What it is:** Session-ending summaries written by your AI assistant. **What goes here:** At the end of any substantive work session, ask your AI to write a handoff note here. The next session starts by reading the most recent one. **Why this is the highest-ROI habit in the vault:** A well-written handoff note eliminates 10-15 minutes of re-explanation. The AI starts already knowing what you were doing, what you decided, and what comes next. **File naming:** `YYYY-MM-DD-topic.md` (e.g., `2026-01-15-site-build-session.md`) **Prompt to generate one:** *"Write a handoff note to 04-Handoffs/[today's date]-[topic].md. Cover: what we did today, what we decided, any open questions, and what the next session should start with."* **See also:** `04-Handoffs/example-*.md` for a worked example. --- ## 05-Patterns/ **What it is:** Reusable formats, templates, and recurring procedures. **What goes here:** Anything you find yourself doing the same way repeatedly. A format for a weekly review. A template for a client brief. A procedure for a deployment. An outline structure you reuse. **File naming:** Descriptive. `weekly-review-format.md`. `client-brief-template.md`. `deploy-procedure.md`. **How the AI uses it:** "Follow the format in 05-Patterns/weekly-review-format.md." --- ## 06-Lessons/ **What it is:** Things you've learned that changed how you work. **What goes here:** Not summaries of articles. Not meeting notes. Genuine lessons — moments where something you learned shifted your approach or revealed a mistake. **Format:** Short. What happened. What you learned. What you'll do differently. Date it. **The rule:** Only add to 06-Lessons/ when you genuinely learned something. Don't add to it just to add to it. An empty folder beats a folder full of generic notes. --- ## 07-Reviews/ **What it is:** Retrospectives, audits, and periodic reviews. **What goes here:** Weekly reviews. Monthly check-ins. Project post-mortems. Audit results. **File naming:** `YYYY-MM-DD-type.md` (e.g., `2026-01-07-weekly-review.md`, `2026-Q1-quarterly-retro.md`) **Prompt for a weekly review:** *"Help me write a weekly review to 07-Reviews/[today's date]-weekly-review.md. Cover: what I accomplished this week, what I didn't finish and why, what I want to prioritise next week, and one thing I want to improve."* --- ## Naming conventions - Folders: `NN-Title/` (numbered for ordering) or `kebab-case/` inside project folders - Notes: `YYYY-MM-DD-kebab-topic.md` for dated notes; `descriptive-name.md` for reference files - No spaces, no CamelCase, no special characters in filenames - `_` prefix for internal files (`_schema.md`, `_template/`) — these are structural, not content --- ## Adapting this vault The structure is intentionally minimal. Common adaptations: - **Add `02-Areas/`** if you have ongoing responsibilities that aren't projects (e.g., health, finances, learning) - **Add subfolders inside 01-Projects/** for complex projects with distinct workstreams - **Add more template files to 05-Patterns/** as you develop recurring formats - **Keep 00-Inbox/ and 00-Memory/ as they are** — these two folders are what make the AI integration work The only rule is: 00-Inbox/ stays the landing zone and 00-Memory/ stays a flat per-fact store. Everything else adapts to your workflow.