The universal sync fallback in stream_tts_to_speaker ran strictly serially
per sentence — synthesize, play, and only then start synthesizing the next
sentence — so every sentence boundary added a full synthesis-time of dead
air. Chunked streamers (elevenlabs/openai/gemini/xai) already avoid this;
every other provider (edge, piper, plugin providers) paid it on each reply
in voice mode and the wake-word loop.
_SyncSentencePipeline overlaps the two: one single-threaded synthesis
worker (sentences stay FIFO; providers never see concurrent calls from
this loop — same effective concurrency as before) feeds one playback
worker through a small bounded queue, so sentence n+1 synthesizes while
sentence n plays. Lookahead is bounded (backpressure + at most a couple of
temp files), stop_event short-circuits both stages, synthesis failures are
isolated per sentence, temp files are always unlinked, and the finally
block flushes the pipeline BEFORE tts_done_event fires so continuous voice
mode never reopens the mic over its own voice. synthesize/play are
resolved late so existing monkeypatch-based tests work unchanged.
Measured with a real local model provider (OmniVoice plugin, Apple
Silicon), same 3-sentence reply, playback simulated at the produced clips'
true durations, best-of-2 interleaved runs under identical load:
serial pipelined
time to first word 10.8s 4.4s
mid-reply dead air 11.2s 1.8s (second gap: 0.03s)
full reply wall 33.2s 17.0s
Tests: 4 new (timestamp-proven overlap, order + per-sentence failure
isolation, stop skips queued playback, temp-file hygiene); the existing
sync-fallback and display-callback tests pass unchanged.
Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Start from main's 13 tests (renamed test_openai_available_reflects_key
to test_openai_available_reflects_audio_key_resolution, added 4 new
tests for xai oauth, elevenlabs secret resolver, openai configured
key, stream cap). Append 12 new regression tests from PR #71084 for
the prefetch pipeline, PCM misalignment, and PortAudio resilience.
Patch platform.system in stream-path tests for main's macOS guard.
Second, deeper pass over tools/gateway/hermes_cli plus first pass over
the trees wave 1 missed (acp, acp_adapter, skills, computer_use, docker,
dashboard, conformance, monitoring, secret_sources, hermes_state,
providers). Same rubric as wave 1 (AGENTS.md test policy); security,
alternation/caching invariants, issue-number regressions, and E2E kept.
Real test-quality fixes found and rooted out along the way:
- tests/tools/test_command_guards.py made real auxiliary-LLM HTTPS calls
(DEFAULT_CONFIG smart-approval leaked in) — pinned approval
mode=manual via autouse fixture: 17.4s → 0.4s.
- test_model_switch_custom_providers.py / test_user_providers_model_switch.py
silently probed live provider catalogs (~2s/test) — stubbed
cached_provider_model_ids/provider_model_ids/fetch_api_models.
- test_telegram_noise_filter.py: 15-platform copy-paste matrix over
shared gateway.run logic → 3 representative platforms (55s → 3.9s).
- test_gateway_shutdown.py: stop()'s 5s interrupt-deadline loop spun on
MagicMock agents — interrupt.side_effect now clears _running_agents
(22s → 1.0s).
- test_gateway_inactivity_timeout.py poll-harness timings shrunk 3-5x
(24s → 1.1s); test_mcp_stability.py backoff/SIGTERM-grace sleeps
patched (15.4s → 2.5s); test_async_delegation.py negative-drain wait
5s → 0.5s.
- test_telegram_init_deadline.py: loop-block margin restored to 1.0s
with rationale comment — the watchdog-dump assertion needs the loop
blocked well past deadline+grace under parallel load (flaked once in
the 40-worker verification run at a 0.2s margin).
Verification: full hermetic suite via scripts/run_tests.sh —
2,438 files, 21,718 tests passed, 0 failed, 293.9s wall.
Suite totals vs original baseline: 46,820 → 19,757 test functions
(−57.8%), wall 583.5s → 293.9s (−50%), subprocess CPU 13,564s → 11,623s.
Follow-up integration for the #47588 salvage, aligning the new streamers
with the post-campaign invariants:
- All streaming key lookups go through _resolve_key -> tts_tool.
_resolve_provider_key -> resolve_provider_secret (config > env/.env >
credential pool, profile-scoped) — never bare get_env_value. xAI
resolves via resolve_xai_http_credentials so OAuth users stream too.
- _capped(): every provider's chunk iterator is bounded at 16 MiB per
sentence, mirroring _read_tts_response_bytes' bounded-upstream-body
invariant on the sync paths.
- Tests updated for the resolver contract + new coverage for credential
routing and the cap.
Salvaged from PR #47588 and rebased onto the post-campaign streaming core:
the StreamingTTSProvider ABC/registry and the ElevenLabs/OpenAI streamers
already live on main (tools/tts_streaming.py), so this ports the pieces
main lacked:
- GeminiStreamer: streamGenerateContent?alt=sse -> base64 PCM chunks
(24 kHz mono int16), reusing main's DEFAULT_GEMINI_TTS_* constants.
- XAIStreamer: WebSocket wss://api.x.ai/v1/tts -> binary PCM frames,
async->sync bridged via the _collect_async test seam.
- tts.streaming.provider config knob: pin one streamer, or 'auto' to
walk the priority list elevenlabs -> gemini -> openai -> xai. Unset
keeps the never-swap-the-user's-voice default.
- docs/streaming-tts.md: architecture, capability matrix, how to add
a provider.
- Unit tests for the knob, SSE parsing, and the WS bridge; key-gated
E2E tests (skipped without credentials).
Refs: #47588
Follow-up to salvaged PR #70307 (@aml1973): OpenAIStreamer now checks
tts.openai.api_key (config.yaml) ahead of the env resolver in both
available() and stream(), completing config parity between the sync
and streaming OpenAI TTS paths.
Use the shared OpenAI audio key resolver and prefer tts.openai.base_url over the global environment fallback in the Desktop streaming path. Add focused regression coverage for credential and endpoint propagation.
mark_speech_interrupted() / take_speech_interrupted(): a one-shot,
TTL'd (120s) latch plus SPEECH_INTERRUPTED_NOTE. Barge-in paths mark
it when they cut live speech; the next turn's submit path pops it and
prepends the note to the model-bound message — API-call local, never
persisted, so history and prompt caching are untouched.
StreamingTTSProvider ABC + registry + resolve_streaming_provider() —
ElevenLabs (pcm_24000) and OpenAI (response_format=pcm) stream chunked
PCM; every other provider keeps its configured voice and falls back to
per-sentence sync synthesis. SentenceChunker is the one incremental
cutter every surface shares: sentence-boundary cuts on the delta
stream, <think> blocks stripped even when split across deltas, short
fragments merged forward so they never stall as tiny clips.