Isogram — AI Text Score (VS Code extension)

Per-line AI-edit scores in the editor, from the Isogram detector. Lines the detector attributes to AI are tinted by class — orange for AI-assisted (AI-edited), red for AI-generated — with intensity by score and the exact numbers on hover. The status bar shows the document verdict; click it to rescore.

More at isogram.hails.info/vscode.

Install

Download the .vsix from isogram.hails.info/vscode, then:

code --install-extension isogram-vscode-0.6.0.vsix

Then run Isogram: Set API Token from the command palette and paste your iso_… API key. The key is stored in the OS keychain via VS Code's SecretStorage, never in settings. Scoring needs a key; keys are issued on request.

What it sends

The extension sends the contents of each scored document, and its file name (not its path — the name steers prose vs. code scoring), to the configured endpoint. It refuses untrusted workspaces, and the endpoint setting is machine-scoped so a workspace cannot redirect your documents or key elsewhere.

How scoring is scheduled

Every eligible document (file or untitled, non-empty, ≤ isogram.maxDocumentKb) is scored after isogram.debounceMs of edit-idle, when it becomes the active tab, and immediately on a manual save. Tab switches share one idle wait, so flipping through several unscored files sends one request, for the one you settle on. The content is SHA-256-hashed first: an unchanged document never re-fires, verdicts seen before are served from an in-memory cache, and a newer edit aborts the superseded request. Documents nobody can see (not shown in an editor, or the window unfocused) are not scored until they are shown.

Prose is scored at token resolution: each line takes the class of the authorship spans covering it. Code falls back to overlapping 512-token windows decoded jointly per line. Lines under the tint threshold (isogram.tintThreshold) get no tint.

Excluded text

Matches of isogram.excludePatterns are cut out of the text before it is sent: they never reach the endpoint, never move the verdict, and are never tinted. A line that is entirely excluded stays untinted; a line mixing excluded and kept text is tinted by its kept text alone. The default excludes HTML comments (<!-- … -->), which rendered markdown never shows; it applies to every document, since a comment in a code file is rare and is also not prose anyone reads. Set the list to [] to score everything.

Matches are removed rather than blanked: a run of spaces where a comment was would still be an input the model reads, and would shift every window after it. The endpoint's offsets are mapped back onto the document, so tints land on the right characters.

Patterns are JavaScript regex sources compiled with flags gmu (^/$ match per line; use [\s\S] to cross lines). The setting is resource-scoped, so a workspace can set its own in .vscode/settings.json, for example to also drop fenced code blocks:

{
  "isogram.excludePatterns": ["<!--[\\s\\S]*?-->", "^```[\\s\\S]*?^```"]
}

An invalid pattern raises one warning, is logged, and is ignored; the others still apply. Changing the list rescores visible documents (from cache when the sent text was scored before).

The endpoint scales to zero: an idle editor costs nothing, and the first score after idle waits for a GPU cold start (up to a minute or two; warm scores return in seconds).

Commands

Settings

Verdicts are probabilistic: treat them as evidence, not proof.

Development

pnpm install
pnpm run typecheck && pnpm run lint && pnpm test
pnpm run package                       # → isogram-vscode-<version>.vsix

pnpm run build bundles src/extension.ts → dist/extension.js with esbuild (CJS — the VS Code extension host does not load ESM entry points, which is why this package has no "type": "module"). Pure logic (hashing, per-line decode, buckets, cache) lives in src/scoring.ts, batch-report building and the concurrency pool in src/batch.ts, both tested with vitest; src/extension.ts is the thin VS Code glue.