Constella is unclaimed —

Constella

Free open source AI Second Brain that gives you unlimited, growing power.·constella.app

Constella is an AI-powered second brain that captures notes, files, and thoughts onto an infinite visual canvas, automatically clustering and connecting related ideas instead of requiring folders. It uses local AI to index the contents of files and apps so users can recall information by meaning rather than filename. Constella syncs sources like Notion, Obsidian, Zotero, Google Drive, Apple Notes, Readwise, and Gmail, and exposes that connected knowledge to AI assistants such as Claude, ChatGPT, and Cursor via an MCP SDK. It offers a free, fully local plan as well as paid Ultra and Mega plans with AI research agents, more integrations, and AI credits.

What it's for

capturing and organizing notes and files without foldersauto-clustering and auto-connecting related ideasrecalling information by meaning instead of filenamessyncing knowledge from Notion, Obsidian, Zotero, Google Drive, Apple Notes, Readwise, Gmail, Apple Messagessurfacing contradictions and agreements across notes/engagementsgiving AI assistants like Claude, ChatGPT, and Cursor shared contextclipping and summarizing web pages via browser overlayresearch agent search across papers (475M+ papers)

Features 15

AI assistant 'Stella' for summarizing and recall inside the canvas
AI Research Agents searching 475M+ papers
Auto-clustering of related notes
Auto-connections between related ideas
Chrome Extension for clipping and summarizing web pages
Contradiction and agreement detection across notes/engagements
Export everything to Markdown, no lock-in
Infinite visual canvas for notes and ideas
Instant one-keystroke capture
Instant Overlay capture/recall shortcut (⌘⇧O)
Local AI indexing of files and apps
MCP SDK to give AI assistants (Claude, ChatGPT, Cursor) access to your knowledge graph
Never trained on user data
Search by meaning rather than filename
Sync with Notion, Obsidian, Zotero, Google Drive, Apple Notes, Readwise, Gmail, Apple Messages

At a glance

free tieropen sourceself-hostableAPI

TypeDesktop app

DeploymentHybrid

PlatformsmacOS

Forresearchers and PhD students, writers, founders, analysts, visual thinkers, neurodivergent thinkers (ADHD/autistic users), firms/teams doing research and diligence work

Integrations

NotionGmailSlackObsidianZoteroGoogle DriveApple NotesReadwiseApple MessagesClaudeChatGPTCursor

Resources

Pricing

Free plan is permanent and local-only, no account needed. Paid plans (Ultra, Mega) billed monthly or yearly (25% off displayed for yearly). 30-day money-back guarantee on paid plans. Payment via major cards or invoicing for labs/institutions.

FreeFree

Free forever, on-device.

No account needed; fully local, on-device only

Ultra$19/mo

Annual billing advertised at 25% off monthly price (page shows a Monthly/Yearly toggle with '25% OFF').

Max 300 AI Connections; 10,000 AI Credits

Mega$39/mo

Annual billing advertised at 25% off monthly price.

Unlimited Connections; 25,000 AI Credits

25% off when billed yearly (per pricing page toggle).