SDK des extensions

A Mentria extension is a single .html file — markup, styles and script in one document. There is no build step, no bundler and no upload: the file lives only on your device, in local storage, and runs on the site the moment you install it.

Démarrage rapide

Copy the file below, drop it into the manager, and open it. It paints itself with the site theme, saves a note to its private storage, and raises a host toast — the three things almost every extension needs.

<script type="application/json" id="mentria-ext">
{
  "id": "starter",
  "name": "Starter",
  "version": "1.0.0",
  "icon": "✨",
  "author": "you",
  "description": "A minimal Mentria extension: theme tokens, a storage roundtrip, and a toast.",
  "permissions": ["storage"],
  "mounts": {
    "tool": {},
    "commands": [
      { "name": "starter", "usage": "starter [text]", "description": "open the starter extension" }
    ]
  }
}
</script>
<style>
  body { margin: 0; padding: 2rem; font-family: var(--ext-font, monospace);
         background: var(--ext-bg, #0b0e11); color: var(--ext-fg, #e6edf3); }
  input, button { font: inherit; padding: .5rem .8rem; border-radius: 6px; }
  input  { width: 100%; box-sizing: border-box; margin-bottom: .6rem;
           background: transparent; color: inherit; border: 1px solid var(--ext-muted, #7d8590); }
  button { background: transparent; cursor: pointer;
           color: var(--ext-accent, #6ef3c5); border: 1px solid var(--ext-accent, #6ef3c5); }
</style>
<h1>My note</h1>
<input id="note" placeholder="type something, then Save…">
<button id="save">Save</button>
<script>
  // window.mentria is injected by the run host before this script runs.
  const { storage, theme, notify, args } = window.mentria;

  // Paint the host theme onto our CSS variables.
  const s = document.documentElement.style;
  s.setProperty('--ext-bg', theme.bg);
  s.setProperty('--ext-fg', theme.fg);
  s.setProperty('--ext-accent', theme.accent);
  s.setProperty('--ext-muted', theme.muted);
  s.setProperty('--ext-font', theme.fontMono);

  const box = document.getElementById('note');

  // Storage roundtrip: last saved note, or text passed on the command line.
  box.value = storage.get('note') || (args && args.args) || '';

  document.getElementById('save').addEventListener('click', () => {
    storage.set('note', box.value);   // persisted under extdata.starter
    notify('saved');                  // host toast, bottom-center
  });
</script>

Install it: open the manager, expand paste source, paste the file, and confirm the trust prompt. Because it declares mounts.tool it also gets a launcher tile, and its starter command shows up in the terminal.

Référence

Manifest

The manifest is a JSON block with id="mentria-ext". It is the only required piece of structure; everything else is ordinary HTML.

The host object — window.mentria

The run host injects a frozen window.mentria before your script executes. Everything an extension can do goes through it.

The run frame is granted the feature policy bluetooth; usb; serial; camera; microphone, so those Web APIs work from inside an extension when the browser and user allow them.

Storage

Each extension owns a private namespace, extdata.<id>, reachable only through window.mentria.storage. It is backed by the browser's localStorage (via MentriaStore), so reads and writes are synchronous and every value must be JSON-serializable.

• Quota is real and shared: localStorage is roughly 5 MB for the whole origin, split across every tool. Keep extension data small; storage.set returns false if the write would overflow.
• Your data is covered by the site's encrypted local backup, and shows up in the Files tool grouped as extension: <id>.
• Removing the extension in the manager also clears its extdata.<id> keys.
• The whole .html is stored too: over 512 KB warns at install, over 1536 KB is rejected outright.

Widgets

Declare mounts.widget and the home launcher shows a live status tile for your extension, named by label and linking to your run page. The tile renders the snapshot object stored under key in your own storage — e.g. storage.set('note', { text: 'bought milk', progress: 0.4 }) — and refreshes on every write.

Anything else under that key — a plain string, an array, an empty text — is ignored silently: the tile simply stays hidden until the key holds a valid snapshot object.

Install & share

• Manager (/tools/extensions/): drop an .html file, choose a file, or paste the source. Every install shows a human trust prompt naming the extension, its version and its declared permissions; updates call out permissions the new version adds or drops, and installing an older version is labeled as a replacement, not an update.
• Share over comms: from an installed row, share hands the file to an open comms session; the peer gets the same trust prompt, attributed from you, before anything installs. If comms is closed it points you there.
• Export: export downloads the stored source back out as <id>.html, so an extension is always portable.