AI assistant

Ask the host's LLM to rewrite the selection or generate new content, watch the response stream into a preview inside a non-modal dialog, then commit it with Replace or Insert below. Trilium's GPL counterpart of the premium AIAssistant feature.

Load the TriliumAiAssistant glue plugin; it pulls in AiAssistantEditing and AiAssistantUI. The feature disables itself when the host configures no stream callback, which is how "no LLM provider set up" reaches the editor.

Files

The host owns everything provider-shaped

The plugin knows nothing about providers, endpoints, authentication or Markdown. It is handed callbacks the same way snippets.definitions and syntaxHighlighting.loadHighlightJs are:

aiAssistant: {
    stream: ( request, onData, signal ) => Promise<AiCompletionUsage | void>,
    diff: ( oldHtml, newHtml ) => string | AiDiffResult,
    quickActions: [ /* groups of predefined instructions */ ],
    menuFooter: [ /* rows for what a run answers to — Trilium hangs the model picker here */ ],
    askIconClass: 'bx bx-message-square-dots',
    sanitizeHtml: html => html   // required
}

stream is the only one whose absence disables the feature; diff merely costs the Changes view, and quickActions merely degrades the toolbar entry from a split button to a plain one.

sanitizeHtml is required and has no fallback — the plugin throws ai-assistant-sanitize-html-required rather than render unsanitized model output. CKEditor ships no sanitizer and asks the integrator for one instead (config.htmlEmbed.sanitizeHtml, whose built-in default only warns and passes through); a top-level config.sanitizeHtml is rejected by the editor outright, so it belongs under this namespace. A built-in strip list was deliberately not written: it would become the real defence the moment a host forgot to configure one, and it reads as safe in review while missing namespaced xlink:href, SVG animation elements and data: URIs. Trilium passes sanitizeNoteContentHtml, the same DOMPurify pass note content gets.

HTML on both ends, with the source alongside

onData is called with the cumulative response HTML on every tick — the same contract the premium AITextAdapter uses. Re-parsing the growing prefix is what keeps the preview renderable mid-stream, since the HTML parser auto-closes tags cut off in the middle.

Its second argument, source, is what that HTML was rendered from, for a host that renders at all. Trilium's model answers in Markdown, and the source is what enters history — so a follow-up hands the model back its own words rather than our rendering of them.

Nothing is written until the user commits

There is no schema and no data conversion because the feature stores nothing: it inserts perfectly ordinary content on commit and is otherwise invisible to the document. Two consequences worth knowing:

• The target is a marker, not the selection. triliumAiTarget is added on open with affectsData: false, so it stays out of the data and the undo stack while surviving focus moving into the dialog — and it is remapped as the user keeps editing behind the dialog, so Replace still hits what was originally selected. An editing-only markerToHighlight tints it.
• A commit is one model.change() and therefore one undo step, marker removal included. The marker is retired inside that change rather than left to the teardown, because teardown hands the pinned range back as the selection and would overrule where insertContent decided to leave it.

Insert below walks out to the outermost block containing the target's end before inserting, so it lands below the whole selection instead of inside it.

The review phase

Renders are throttled to RENDER_THROTTLE_MS (80 ms) with the last chunk always flushed — the stream arrives far faster than a re-parse of the whole prefix is worth doing.

The diff is computed once, when the run finishes, never against a partial stream: a half-streamed response diffs as a sea of deletions. Which view the review opens on is decided in this order:

1. The quick action's own reviewView, for actions whose answer replaces its source by definition (translation, summary, diagram).
2. AiDiffResult.isUnchanged — the review says "nothing to change" outright instead of showing a diff with no marks in it, which reads as a diff that failed.
3. AiDiffResult.rewriteRatio against REWRITE_RATIO_THRESHOLD (0.5). Past half, the response itself is the thing worth reading.

A renderer returning a bare string is treated as having rewritten nothing, which is what a plain word-level diff amounts to.

The preview is outside the editor's pipeline

Response HTML reaches the preview through innerHTML, so it gets the configured sanitizer on the way in — and then _enrichPreview renders what the pipeline would otherwise have done for it:

• Math, when config.math is present, through the same renderEquation the widget uses.
• Mermaid, when MermaidEditing is loaded and config.mermaid.lazyLoad is set, through the now-public renderMermaid. This is why that function is exported at all — the review has to show what committing will produce, not the language-mermaid code block it produces it from.

Both are best-effort: a missing plugin or config just leaves the block as it came.

The menu is rebuilt, not rebound

updateQuickActions() and updateMenuFooter() replace the lists and invalidate the rendered menus so they redraw on next open. That is what lets the host add a custom action, or change which model is ticked, without rebuilding the editor — and why consumers outside this folder (the / palette, the right-click menu) read AiAssistantUI#quickActions rather than config.aiAssistant.quickActions: the config only seeded the list, and the content languages behind Translate can be changed from inside the editor.

Groups render either inlined at the top level or as a submenu (submenu: true). An inlined group loses its heading — CKEditor's nested-menu definition has only buttons and submenus, no group separators — which suits actions that already read as commands ("Fix typos") and not those that only make sense under theirs ("Romanian"). The latter is also why AiQuickAction.commandLabel exists: the / palette shows actions away from their heading.

Reaching the feature from outside

Ctrl+Shift+K opens the prompt. Neither idiom the feature would have liked was free — Ctrl+K creates a link here as in every other editor, and Ctrl+J is Trilium's Jump to note — so it keeps the K that Cursor, Linear and Slack made the key for "ask for something" without taking either.

Provenance

Trilium's own, written from scratch; there is no upstream to track and no third-party license file next to it. What it borrows from the premium AIAssistant is the shape of the integration rather than any code: the cumulative-HTML streaming contract is AITextAdapter's, the host-supplied sanitizer follows htmlEmbed's, and AiQuickAction is the GPL counterpart of AICommandDefinition.