Key Concepts
Atlas combines a few distinct ideas that work together. This page explains them so you have a mental model before diving into the details.
A vault is a folder on your computer where Atlas stores everything. It’s full of plain markdown (.md) files — no database, no proprietary format.
Atlas reads your vault to answer questions, find relevant notes when you’re chatting, and write new content when you ask it to. But your files never leave your machine unless you choose to sync or share them yourself.
You can open your vault in any text editor, back it up with any tool, and keep it in a Git repository. Your data is always yours.
Notes are .md files in your vault. Atlas works with standard markdown, plus a few conventions:
- Wiki-links:
[[Note Title]]creates a link from one note to another - Tags:
#tagadds a tag to any note - Frontmatter: YAML metadata at the top of a file (between
---lines) for structured fields like date, status, or type - Tasks:
- [ ] task itemcreates a checkbox task that Atlas can track and toggle
You can write notes manually or ask the agent to create and edit them for you.
The agent is the AI assistant built into Atlas. It’s not a chatbot that just answers questions — it can take actions in your vault.
The agent reads and writes files, searches your notes, manages your contacts, sets reminders, creates calendar events, and more. It does this using tools (see below).
When you have a conversation with Atlas, the agent is always working behind the scenes: searching your vault for context, deciding which tools to use, and making sure its responses are grounded in your actual information.
Tools are actions the agent can perform. When you ask Atlas to do something, it chooses the right tool (or sequence of tools) to get it done.
Atlas has 39+ tools across several categories:
| Category | Examples |
|---|---|
| Notes | Create, read, edit, move, search notes |
| Memory | Remember facts, search memory, update your profile |
| Tasks | Add tasks, toggle completion, generate a daily report |
| Daily notes | Open today’s note, add to it |
| CRM | Look up contacts, find organizations |
| Calendar | List upcoming events, create events |
| Weather | Get current conditions and forecast |
| Voice | Create voice notes from recordings |
| Scheduling | Set reminders, create recurring tasks |
Tools run locally on your machine — there’s no round-trip to a server to execute them. The agent decides which tools to use, but the execution happens right on your computer.
Memory
Section titled “Memory”Atlas remembers things across conversations. This isn’t just chat history — it’s a persistent knowledge base about you, stored as markdown files in your vault.
Memory is organized into a few layers:
- Facts: Things you’ve told Atlas, like your job, preferences, or important context
- Goals: What you’re working toward
- Relationships: Notes on people in your life
- Projects: Active work you’ve mentioned
Over time, Atlas also generates a snapshot — a short summary of who you are and what you’ve been focused on lately. This gets included in every conversation so Atlas doesn’t start from zero each time.
Memory is stored in atlas/memory/long-term/facts.md. You can read and edit it directly.
Sessions
Section titled “Sessions”A session is a single conversation thread. Sessions have a few important behaviors:
- Auto-resume: If you close and reopen Atlas within 4 hours, it picks up where you left off in the same session
- Topics: After a few messages, Atlas generates a topic title for the session so you can find it later
- Summaries: When a session ends, Atlas writes a summary to long-term memory so important things aren’t lost
- History: The full transcript of each session is saved in
atlas/memory/sessions/as a JSONL file
You can browse past sessions and review what was discussed. Sessions are part of your vault — plain files you can read anytime.
RAG (Retrieval-Augmented Generation)
Section titled “RAG (Retrieval-Augmented Generation)”RAG is the mechanism that makes Atlas’s AI responses relevant to your specific notes rather than generic.
Here’s what happens every time you send a message:
- Atlas searches your vault for notes related to your message
- The most relevant notes are included as context in the prompt sent to the AI
- The AI answers based on both its training and your actual notes
This search uses a hybrid approach: semantic search (understanding meaning) combined with keyword search, fused together for the best results. It uses a local ONNX embedding model — no internet required for search.
The practical effect: if you’ve written a note about something, Atlas knows about it and can reference it accurately. The more notes you have, the more personalized and accurate Atlas becomes.
Local vs Cloud
Section titled “Local vs Cloud”Atlas has two distinct operating modes, and it’s important to understand the distinction:
Local features run entirely on your computer — no internet required, no account needed, no subscription:
- Vault management and note editing
- Hybrid search across your vault
- CRM (contacts, organizations, topics, relationship graph)
- Plugins
- Templates
- Daily notes and tasks
- Scheduling and reminders
- File watcher (auto-indexing new files)
- Calendar integration (OAuth, runs locally)
Cloud features require a subscription and send requests to Atlas’s servers, which forward them to OpenAI:
- AI chat (the LLM powering the agent’s responses)
- Speech-to-text (voice input via OpenAI Whisper)
- Text-to-speech (voice output)
- Wake word detection
- Drumbeat (ambient awareness — periodic background check-ins)
For a full breakdown of what’s included at each tier, see Free vs Paid Features.