Grammalecte

French grammar and spell checking inside Obsidian, powered by Grammalecte. Mistakes are underlined while you write; click one to read the explanation and apply a correction.

[!WARNING] This plugin is vibecoded. It was written almost entirely by an AI agent, with little to no human review. It may break, lose your place, mangle text when applying a suggestion, or do something else entirely. Use it at your own risk, on a vault you back up. No warranty, no support, and no responsibility is taken for anything that happens to your notes or your machine — see the licence.

Features

• Grammar and spelling mistakes underlined directly in the editor: blue for grammar, red for spelling.
• Click an underline for Grammalecte's explanation, its suggested corrections, and a way to ignore that rule or add the word to your dictionary.
• Checks as you type (debounced), or only when you ask.
• Three interchangeable backends, including one that runs fully offline and on mobile.
• Markdown-aware: code, math, link targets and frontmatter are not checked.

Install

This plugin is not in the community catalogue. Copy main.js, manifest.json and styles.css into <vault>/.obsidian/plugins/grammalecte/, then enable Grammalecte in Settings → Community plugins.

To build from source:

pnpm install
pnpm run build

Choosing a backend

Grammalecte itself is not part of the plugin. Pick where the checking happens in Settings → Grammalecte → Grammar checker; everything else behaves the same.

Local server

Download the Grammalecte Python package from grammalecte.net, then start the server:

python3 grammalecte-server.py -p 8080

Set the server URL to http://localhost:8080 and press Test in the settings — it reports the Grammalecte version when the connection works.

Remote server

Any host running the same grammalecte-server.py works, for example a server of your own. Your note text is sent to it in full, so only use an instance you trust. This is the simplest option on mobile.

Bundled engine (offline)

Choose Bundled engine and press Install / update. The plugin downloads the official Grammalecte browser extension from addons.mozilla.org and extracts the ~9 MB of engine and dictionary files it needs into <vault>/.obsidian/plugins/grammalecte/engine/.

Checking then runs inside Obsidian, in a Web Worker, so typing stays responsive. Nothing leaves your device. The first check after each start takes a moment while the dictionary loads, and the loaded engine costs roughly 40 MB of heap (measured on desktop) — on an old phone, a remote server may be the better trade.

Remove deletes the downloaded files again.

Using it

• Underlines appear as you stop typing. Click one to open the correction menu:
  • a suggestion applies it immediately;
  • Ignore this rule silences that Grammalecte rule everywhere;
  • Add to personal dictionary silences that word everywhere;
  • Learn more opens Grammalecte's explanation page, when the rule has one.
• The ribbon icon (✓) checks the current note on demand.
• The status bar shows the issue count for the current note, no issue, or error — hover it for the reason.

Commands

Assign hotkeys to them in Settings → Hotkeys.

Settings

Rule ids look like g3__conf_marre_mare__b2_a1_1; the Ignore this rule menu entry fills this list for you.

How it works

• The note is read from the editor, Markdown syntax is replaced by spaces (so every offset still matches the original text), and the result is sent to the chosen backend.
• Grammalecte returns errors with offsets relative to each paragraph; the plugin maps them back onto the document and draws them as CodeMirror decorations, which follow your edits until the next check.
• If the document changes while a check is in flight, the result is discarded rather than applied at stale positions.
• The bundled engine is the official Grammalecte JavaScript build, evaluated in a worker with its file loader pointed at data the plugin reads from the vault.

More detail for contributors is in AGENTS.md.

Development

pnpm install
pnpm run dev     # watch build into main.js
pnpm run build   # type-check, then production bundle
pnpm run lint
pnpm run test

Tests that need a Grammalecte server are skipped unless one is reachable (GRAMMALECTE_SERVER overrides the URL), and the engine tests are skipped until the engine is installed in engine/.

Credits

Grammalecte is written by Olivier R. and released under the GPL v3. This plugin only drives it: the engine is downloaded from the official releases and is not redistributed here.

Licence

MIT — see LICENSE. In short: do what you like with it, and it comes with absolutely no warranty. The author is not liable for any damage, data loss or other trouble arising from its use.