hermes-relay/RELEASE_NOTES.md

Hermes-Relay v0.5.1

Release Date: April 18, 2026 Since v0.5.0: Voice-focused patch release — TTS quality pass, conversational barge-in, silence-based auto-stop, plus a bootstrap crash fix

The voice release. v0.5.0 shipped the bridge polish; v0.5.1 makes voice mode feel like a real conversation. Gapless ExoPlayer playback, client + relay sanitizers so the agent stops reading emoji and markdown fences aloud, sentence-prefetch so there's no dead air between chunks, barge-in so you can interrupt by just speaking, and silence-based auto-stop so Continuous mode actually ends your turn when you stop talking.

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📥 Download

v0.5.1 ships in two build flavors. APK filenames are version-tagged:

Flavor	File	Who it's for
sideload (recommended)	hermes-relay-0.5.1-sideload-release.apk	Full feature set — bridge channel, voice intents, unattended access, vision-driven android_navigate. Installs alongside the Play build with a .sideload applicationId.
Google Play	hermes-relay-0.5.1-googlePlay-release.aab	Conservative feature set (chat, voice, safety rails — no agent device control) to match Play Store's Accessibility policy.
googlePlay APK	hermes-relay-0.5.1-googlePlay-release.apk	Parity + diff tooling — not the primary download.
sideload AAB	hermes-relay-0.5.1-sideload-release.aab	Parity + diff tooling — not the primary download.

Verify integrity with SHA256SUMS.txt from the same release. See the Sideload guide for install steps.

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✨ Highlights

Voice quality pass

• Gapless TTS playback. Swapped MediaPlayer for Media3 ExoPlayer with a persistent instance and addMediaItem queuing. No more 200–400 ms silence between sentence chunks, no more pop / click on chunk boundaries.
• Client + relay text sanitizers. Assistant output is stripped of markdown fences, tool-call annotations (`💻 terminal`), URLs, and emoji before hitting ElevenLabs — on the relay (plugin/relay/tts_sanitizer.py) and on the phone (VoiceViewModel.sanitizeForTts). The chat UI still shows emoji; only the voice path is cleaned. Solves "agent reads colon rocket out loud" and "agent reads https colon slash slash github dot com."
• Sentence coalescing + secondary-break chunking. Minimum 40-char chunks with 800 ms idle flush; ellipses / dashes treated as soft breaks when the primary sentence end is far away. Keeps prosody natural without waiting for a full paragraph.
• Prefetch synth-while-playing pipeline. Two coroutines in a supervisorScope — one synthesizing the next sentence while the previous one plays. Channel-backed with capacity 2 so the player never starves.

Voice barge-in (off by default, opt-in via Voice Settings)

• Silero VAD + AcousticEchoCanceler + hysteresis. Duplex AudioRecord (VOICE_COMMUNICATION source) monitored by a Silero VAD engine with 2–3 consecutive-frame hysteresis. AEC binds to the ExoPlayer audio session id so the VAD sees your voice, not the agent's playback echo.
• Soft-duck → hard-cut interrupt. Single VAD positive triggers a 30 % volume duck; confirmed hysteresis pass hard-cuts playback and starts a new listening turn. 500 ms duck-watchdog un-ducks on a single-frame false positive so stray clicks only briefly dip the volume.
• Optional resume-from-next-sentence. After a barge-in interrupt, a 600 ms silence watchdog checks whether the user actually continued speaking. If not (cough, false positive, stray laugh), the remaining un-played sentences are re-queued. Toggle in Voice Settings.
• Sensitivity picker (Off / Low / Default / High) with an always-visible AEC compatibility badge so users know when their device's echo canceler isn't loaded (affects false-positive rate on some Samsung / Motorola / older Pixel builds).

Silence-based auto-stop for listening turns

• The silenceThresholdMs preference is finally wired. Previously the Settings slider persisted a value nothing ever read — Continuous mode would re-arm the mic after TTS drained and then wait forever for a manual tap to send. Now VoiceViewModel.startListening() arms a watchdog that polls amplitude every 150 ms and auto-calls stopListening() after the configured silence window (default 3 s) following at least one above-floor frame.
• Grace window — auto-stop never fires before the user's first above-floor frame, so "tap mic, take a beat" doesn't insta-close the turn.
• Skipped in Hold-to-Talk. The physical release is the authoritative stop there; auto-stopping mid-hold would be surprising.

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🔧 Fixes

• "Final short sentence with emoji not spoken in Continuous mode." Race in maybeAutoResume where Continuous mode's startListening() → player.stop() clobbered the still-in-flight final chunk's playback pipeline. Fixed with an AtomicInteger gate on the synth queue; auto-resume now defers until the TTS pipeline actually drains.
• Continuous mode didn't persist across app restarts. VoiceViewModel never subscribed to VoicePreferencesRepository.settings.interactionMode, so cold starts always defaulted to Tap-to-Talk regardless of the saved pref. Now subscribes on initialize and mirrors the saved value into uiState.
• Bootstrap gateway crash: 'tuple' object has no attribute 'freeze'. hermes_relay_bootstrap/_command_middleware.py::maybe_install_middleware was replacing aiohttp's FrozenList with a plain tuple, which broke when AppRunner.setup() later called .freeze(). Switched to in-place app._middlewares.append(middleware). 31/31 middleware tests pass.

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🧪 Verification checklist (post-install)

• Voice mode → ask the agent a multi-sentence question. No gap / click between sentences; no emoji or markdown spoken aloud.
• Speak over the agent mid-response with barge-in ON → playback cuts within ~100 ms, a new listening turn starts.
• Briefly cough during playback with barge-in ON and "Resume after interruption" ON → playback ducks briefly but resumes from the next unplayed sentence.
• Voice Settings → Interaction Mode → Continuous → force-stop the app → relaunch → Voice mode still comes up in Continuous.
• Voice Settings → Silence Threshold slider at 3 s → start a Tap-to-Talk turn → speak one sentence → stop talking → within ~3 s the turn auto-submits.
• Device without AEC → Voice Settings shows the compatibility badge next to the Barge-in section.

🧩 Known — test suite deferred

8 new voice/audio unit tests added in this release are @Ignore'd pending a test-infra follow-up. See issue #32 for the root-cause breakdown (coroutine .cancel() without .join() + Media3 static init on pure JVM + Robolectric classloader leakage). No app-behavior impact — the tests describe intent + assertions for the new voice code and will be un-@Ignore'd once the separate-source-set split lands. On-device smoke testing (by Bailey, Samsung) validated the feature behavior.

See CHANGELOG.md for the full file-level diff and DEVLOG.md for the per-feature session narrative.

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