Local-first · Open-Source · Private
Your notes,
Capture ideas with voice, find anything with semantic search, and let AI organize your thoughts — all on your device.
How it works
From thought to organized knowledge — in seconds
No complex setup. No manual filing. Just capture and let Tentacle do the rest.
Record your voice
Speak your thoughts. No typing needed — Tentacle captures audio directly on your device.
AI organizes everything
Transcribed, tagged, and indexed automatically. Your note is searchable before you blink.
Enable cloud sync to access your notes on any device, encrypted end-to-end.
Your notes never leave your device unless you want them to
Tentacle is built on a local-first architecture. All your notes, embeddings, and search indexes are stored locally. We can't read your notes even if we wanted to.
- All data stored in a local vector database
- Embeddings computed on-device
- Optional end-to-end encrypted cloud sync
- Export to Obsidian anytime
- Open source and auditable
Everything you need to capture and organize ideas
Powerful features that work locally on your device, with optional cloud AI when you need it.
Semantic Search
Find notes by meaning, not just keywords. Local embeddings understand what you're looking for — no cloud required.
Voice Capture
Capture ideas instantly with voice recording. Transcribed locally using Whisper or with your own OpenAI key.
Auto-Tagging
Let AI automatically organize your notes with relevant tags. Free users can BYOK, Pro users get it included.
Markdown Support
Write in Markdown with a beautiful editor. Export to Obsidian or any other Markdown-compatible tool.
Ask questions across all your notes. Get answers sourced from your own thoughts, not the internet. Your personal research assistant.
Access your ideas on any device. End-to-end encrypted cloud sync means your notes are available everywhere, but readable only by you.
Works with any agent
Tentacle also ships as a CLI app, so your agents can use your knowledge base directly.

Agent Zero

OpenClaw
Claude Code

Codex

OpenCode
# save a note
$ echo "Use JWT with 7-day refresh tokens" | tentacle create --title "Auth decision" --folder projects --json
✓ Saved as id: a1b2c3d4
# find it later
$ tentacle search "auth decision" --json
1) Auth decision id: a1b2c3d4
# read full content
$ tentacle read a1b2c3d4 --json
{"title":"Auth decision","content":"Use JWT with 7-day refresh tokens"}
# optional: summarize with your LLM
$ tentacle read a1b2c3d4 --json | claude "summarize in one sentence"
→ JWT auth with 7-day refresh tokens for simple stateless sessions.
$
Simple, transparent pricing
Start free, upgrade when you need more power. No hidden fees.
Free
$0
Perfect for getting started with local note-taking
- Local note storage
- Semantic search (local embeddings)
- Voice capture with BYOK
- Manual tagging
- Markdown export to Obsidian
- BYOK auto-tagging (with friction)
Most Popular
Pro
$10/month
Unlock the full power of AI-powered note-taking
- Everything in Free
- Auto-tagging (no API key needed)
- Chat with knowledge base (RAG)
- Cloud sync across devices
- Mobile app access
- Priority support
Pro billed monthly. Cancel anytime.
Ready to build your second brain?
Join people who trust Tentacle to organize their thoughts, capture ideas, and find knowledge instantly — all on their own device.
No credit card required. Free forever.