Reply by Voice (talk back to a spoken recap)

What it is

In development — hidden by default. Reply by Voice ships behind the narration-voice-reply unreleased-feature gate (setting narrationVoiceReplyEnabled, default off; reveal via Settings → Lab). It also requires Voice Input (voiceEnabled) to capture. Not visible to users until it is flipped to shipped.

What it is

Reply by Voice is the reply sibling of Spoken Narration. Where narration plays the AI's spoken recap, Reply by Voice lets you talk back: a mic button sits beside each message's narration play button, and tapping it opens a window where you speak, watch a live transcript appear, edit it if the speech-to-text slipped, and send it to that session as your reply — voice instead of typing, right at the recap moment.

It reuses the app's existing voice input end to end (mic capture, local Whisper or cloud speech-to-text, and the normal send path) — there's no new voice engine.

On mobile (the phone / web client): the mic button and window work on a phone too, over the same secure connection. Mobile mic capture is best-effort — it depends on the phone browser allowing microphone access, and isn't guaranteed on every browser until tested on a real device.

Where to find it

The mic button sits beside each message's narration play button, on messages that carry a spoken recap. Its own controls are in Settings → Voice & Speech → Reply by Voice, visible only while the feature is revealed.

How it behaves

How it works

1. Talk. Opening the window takes over the microphone and starts dictation; your words appear live and each settled phrase is added to an editable box. Opening the window also stops the recap audio so the mic doesn't hear the AI talking over you.
2. It cleanly owns the mic. While the window is open it is the sole owner of the mic, so the app's always-listening voice system stands down — your spoken reply can never be double-sent or misrouted into the wrong session.
3. Review or auto-send (your choice). By default you review and edit, then tap Send. You can switch to auto-send in settings, which sends after you pause (with a short, cancelable countdown, and only for a long-enough phrase so a stray noise can't fire a paid reply).
4. Send. Your (edited) words go to that session exactly as if you'd typed them.

If Voice Input is off, the window shows a clear "turn on Voice Input" prompt instead of failing silently.

Settings

Settings → Voice & Speech → Reply by Voice (visible only while the feature is revealed): the enable toggle (narrationVoiceReplyEnabled) and the send-behavior toggle Auto-send when you pause (narrationVoiceReplyAutoSend, default off = review-first).

Relationship to Spoken Narration

The mic button appears exactly where a narration play button does — on agent messages that carry a spoken recap — so Reply by Voice only shows up where there's something to reply to. Engineering invariants (the mic-ownership fence, the release drain, capture reuse, the narration-echo stop, the send-behavior guards) are pinned by narration-voice-reply-contract.md; the shared voice-routing rules live in voice-capture-routing-contract.md.

Related

• spoken-narration.md — playing the AI's spoken recap, which this feature replies to.
• reply-to-start-nudge.md — the other way a reply starts something.
• voice-and-tts.md — the voice and speech surface this feature reuses to capture your words.