Hypha

free · open-source · local-first

Markdown notes you own. Agent access you can trust.

A fast live-preview editor, backlinks, and a knowledge graph over ordinary .md files on your disk. And when you want AI in your notes, agents read them right on your machine — never in someone else's cloud.

Download for macOSAll platforms

Free, no account needed · macOS and Linux · also on Android

Hypha's live-preview markdown editor showing a Reading list note with rendered wikilinks, tags, tasks and a code block, next to the file tree sidebar

the daily tool

Everything a serious markdown notes app owes you

A knowledge graph over real files

Wikilinks, backlinks, and an interactive graph view — computed from the plain .md files in your folder, never from a private database. Unresolved links show you where your thinking wants to go next, and a local graph maps each note's neighborhood.

Hypha's knowledge graph view rendering notes as connected nodes, with the file tree sidebar and graph controls for full vault, local view and filters

Search that respects a big vault

Full-text search with highlighted snippets, plustag:, path:, file: and quoted phrases — indexed entirely on your machine, instant even in a vault with thousands of notes. A fuzzy quick switcher jumps to anything.

Hypha's search panel showing full-text results with highlighted snippets across notes, next to the open Reading list note

  • Live-preview editing

    Write markdown, read it rendered — wikilinks, tags, tasks, embeds, callouts, code and math display in place, while the file on disk stays clean, plain text you could open anywhere.

  • Templates & daily notes

    One keystroke opens today's note; templates keep captures consistent. The habit loop that makes a vault stick, built in.

  • Your files, no lock-in

    A vault is just a folder of notes on your disk. Open it in any editor, back it up any way you like, take it anywhere. Delete the app and you lose nothing — ever.

  • Sync that can't read your notes coming

    Optional end-to-end encrypted sync across your devices: notes are encrypted before they leave your machine, so no one else can read them — not even us. Full version history included.

agent-native, not ai-flavored

Your agents can read your vault.
Your notes never leave your machine.

Ask Claude — or any AI assistant you already use — about your own notes: "what did I decide about X?", "summarize my reading list". Connect it with one command, and it reads your vault directly on your machine. No cloud, no upload, no account — and read-only, so nothing can rewrite your notes behind your back.

# connect your notes to Claude — one command
$ claude mcp add hypha -- hypha mcp ~/notes
  • Rename anything — nothing breaks. Move a note, rename it, reorganize your whole folder: links, backlinks and what your agents remember all keep pointing at the right note.
  • Answers, not data dumps. Agents fetch exactly the passage they need — never your whole vault — so answers come back fast and your notes are not sprayed into a chat window.
  • Agents see what you see. The app, the search and your AI all read the same files on your disk. No exports, no copies, no "sync to our servers first".

questions

Frequently asked

Is Hypha free?

Yes. Hypha is free and open source, with no account, no trial and no feature gates. Development will be funded by an optional paid sync service for people who want their notes on every device — the app itself never depends on it and stays free.

What platforms does Hypha run on?

Hypha runs on macOS and Linux on desktop, and on Android on mobile. iPhone and iPad are designed and coming. Every app works over the same folder of markdown files.

Where are my notes stored?

In a folder you choose on your device, as plain markdown (.md) files. Your files are the only source of truth — you can open the same folder with any other editor, back it up however you like, and if you ever delete Hypha you keep every note, exactly as you wrote it.

Does Hypha work offline?

Completely. Hypha is local-first: writing, search, backlinks and the graph all run on your machine with no account and no internet connection. There is nothing to sign into and no server between you and your notes.

Can AI agents read my notes? Is that private?

If you want them to, yes — and it stays private. Hypha has agent access built in: connect Claude or any compatible AI assistant with one command, and it reads your notes directly on your machine. Nothing is uploaded, there is no cloud AI inside Hypha, and access is read-only — nothing can rewrite your notes behind your back.

What is Hypha Sync?

An optional, paid service (in development) that keeps your notes in sync across devices with end-to-end encryption: notes are encrypted before they leave your device, so not even we can read them. Until it ships — and after — you can also sync your folder with any tool you already trust.

Is Hypha open source?

Yes. The entire app — editor, search, graph and agent access — is open source under the AGPL-3.0 license, developed in public. You can read every line of the code that touches your notes.

get hypha

Start owning your notes
in the next minute.

Download Hypha, point it at a folder, and write. Free, open source, no account — your first note is a plain .md file you will still own in thirty years.

Also on Android

Free & open source · AGPL-3.0 · your notes stay on your devices