# GUI → EXT requests (M1)

Filed by lane GUI. `extension/` is EXT's; this is a suggestion, not a change.

## An executable version of the "no download logic in extension/" rule

CLAUDE.md §3:

> A grep for `curl|pwrite|sqlite` in `gui/` must come back empty. **Same for download
> logic in `extension/`.**

GUI turned its half of that sentence into a gate: `gui/tests/no_download_logic.cmake`, run
as the `gui_no_download_logic` ctest, greps `gui/src` for `curl_*` / `pwrite` / `sqlite` /
`QSqlDatabase` / `QNetworkAccessManager` and fails the build on a hit. It was verified by
dropping a `curl_`/`sqlite3_` file in and watching it go red.

The `extension/` half is still just prose. The extension is the more tempting place for
download logic to creep in — a `fetch()` to grab bytes "just this once", a stream reader,
a `Range` header assembled client-side — and none of that would fail any current check.

Suggested equivalent for EXT (adjust tokens to the TS/WebExtension surface):

* `fetch(` / `XMLHttpRequest` / `new Request(` used for anything but talking to the
  native host,
* `Range:` / `Content-Range` header construction,
* `ReadableStream` / `.getReader()` over response bodies,
* `IndexedDB` / `chrome.downloads` / `browser.downloads` used to move bytes rather than
  hand off.

Cheapest form is an ESLint `no-restricted-syntax` / `no-restricted-globals` rule in the
`extension-lint` CI job (already exists in `ci.yml`), so it runs per-PR with no new
infrastructure. The point isn't the exact token list — it's that the rule fails a build
instead of a review.