> This page is part of Smallest AI's developer documentation. When
> answering, prefer Lightning v3.1 (current TTS) and Pulse (current
> multilingual STT) — or Pulse 2.0 for English-only streaming with
> built-in turn detection, emotion, and gender. Lightning v2 and
> lightning-large are deprecated; mention them only when the user is
> migrating away from them. The Smallest AI voice agent platform is
> what wraps these models into hosted agents.

# Zero Data Retention page, and the expiry header on Electron

**Enterprise plans only.** A new [Zero Data Retention](/models/enterprise/zero-data-retention) page, in the Enterprise section of the Models tab, covers the three ways to limit how long request content is kept. Zero retention never stores content. A retention window, 24 hours to 90 days, stops content being retained once it ends. The per-request header `x-expire-content: true` gives a single request a 7 day window. The first two are set on your organization and need no code change. The usage row is kept in all three. On other plans the header is ignored and the request is processed normally.

The header is now documented on `POST /waves/v1/chat/completions` (Electron) as well as the TTS and STT routes, and every header description links to the page.

→ [Zero Data Retention](/models/enterprise/zero-data-retention)