diff --git a/tools/transcription_audio.py b/tools/transcription_audio.py
index f34e052ed8..00d6c25c25 100644
--- a/tools/transcription_audio.py
+++ b/tools/transcription_audio.py
@@ -58,15 +58,14 @@ _STT_M4A_ENCODE_ARGS = ("-vn", "-ac", "1", "-ar", "16000", "-c:a", "aac", "-b:a"
 def _run_ffmpeg_stt_encode(ffmpeg: str, input_path: str, output_path: str, *, audio_filter: Optional[str] = None) -> None:
     """Run the shared STT m4a encode, optionally with an ``-af`` filter. Raises on failure; callers own the semantics."""
     filter_args = ["-af", audio_filter] if audio_filter else []
-    _run_quiet([ffmpeg, "-y", "-i", input_path, *filter_args, *_STT_M4A_ENCODE_ARGS, output_path], timeout=120)
+    _run_quiet([ffmpeg, "-y", "-i", input_path, *filter_args, *_STT_M4A_ENCODE_ARGS, output_path],
+               timeout=120)
 
 
 def _transcode_audio_for_stt(file_path: str, work_dir: str) -> tuple[Optional[str], Optional[str]]:
     """Transcode to a compact 16 kHz mono AAC/m4a for STT upload; ``(converted_path, None)`` or ``(None, error)``.
-
-    Newer OpenAI models reject containers ``whisper-1`` accepted (notably Ogg/Opus
-    voice notes) and gateway downloads may carry a misleading extension.
-    """
+    Newer OpenAI models reject containers ``whisper-1`` accepted (notably Ogg/Opus voice notes) and
+    gateway downloads may carry a misleading extension."""
     from tools.transcription_tools import _find_ffmpeg_binary, _run_ffmpeg_stt_encode
     ffmpeg = _find_ffmpeg_binary()
     if not ffmpeg:
@@ -207,18 +206,17 @@ _CLOUD_TRIM_MIN_INPUT_SECONDS = 12.0
 
 
 def _probe_audio_duration(file_path: str) -> Optional[float]:
-    """Return the audio duration in seconds via ffprobe, or None.
-
-    Canonical sync probe; ``gateway/run.py._probe_audio_duration`` and the
-    Telegram adapter carry local variants — keep the command shape in sync.
-    """
+    """Return the audio duration in seconds via ffprobe, or None. Canonical sync probe;
+    ``gateway/run.py._probe_audio_duration`` and the Telegram adapter carry local variants — keep
+    the command shape in sync."""
     from tools.transcription_tools import _find_ffprobe_binary
     ffprobe = _find_ffprobe_binary()
     if not ffprobe:
         return None
     try:
-        return float(_run_quiet([ffprobe, "-v", "error", "-show_entries", "format=duration", "-of",
-                                 "default=noprint_wrappers=1:nokey=1", file_path], timeout=30).stdout.strip())
+        probe = _run_quiet([ffprobe, "-v", "error", "-show_entries", "format=duration", "-of",
+                            "default=noprint_wrappers=1:nokey=1", file_path], timeout=30)
+        return float(probe.stdout.strip())
     except Exception:  # noqa: BLE001 - probe is best-effort
         return None
 
@@ -235,9 +233,7 @@ def _cloud_trim_settings(stt_config: Dict[str, Any]) -> tuple[bool, int, int]:
 
 def _trim_silence_for_cloud_stt(file_path: str, stt_config: Dict[str, Any]) -> Optional[str]:
     """Return a silence-trimmed copy of *file_path* for cloud upload, or None (= upload the original).
-
-    On success the caller owns deleting the returned file's parent directory.
-    """
+    On success the caller owns deleting the returned file's parent directory."""
     from tools.transcription_tools import _find_ffmpeg_binary, _probe_audio_duration, _run_ffmpeg_stt_encode
     enabled, threshold_db, keep_ms = _cloud_trim_settings(stt_config)
     if not enabled:
@@ -277,8 +273,8 @@ def _trim_silence_for_cloud_stt(file_path: str, stt_config: Dict[str, Any]) -> O
             logger.debug("Cloud STT silence trim discarded for %s: saves <%.0f%% (%.1fs -> %.1fs)",
                          name, _CLOUD_TRIM_MIN_SAVING * 100, original_duration, trimmed_duration)
             return None
-        logger.info("Trimmed silence from %s before cloud STT upload (%.1fs -> %.1fs, -%d%%)",
-                    name, original_duration, trimmed_duration, round((1 - trimmed_duration / original_duration) * 100))
+        logger.info("Trimmed silence from %s before cloud STT upload (%.1fs -> %.1fs, -%d%%)", name,
+                    original_duration, trimmed_duration, round((1 - trimmed_duration / original_duration) * 100))
         keep_result = True
         return trimmed_path
     except Exception as exc:  # noqa: BLE001 - trim is best-effort
diff --git a/tools/transcription_cloud.py b/tools/transcription_cloud.py
index 5627b8a410..aca2f9a2de 100644
--- a/tools/transcription_cloud.py
+++ b/tools/transcription_cloud.py
@@ -38,10 +38,8 @@ def _has_xai_stt_credentials() -> bool:
 
 def _with_openai_client(api_key: str, base_url: Optional[str], file_path: str, log_label: str, body):
     """Run ``body(client)`` on a fresh OpenAI SDK client (30s timeout, no retries); always closed.
-
-    Errors map to the shared envelope. APIConnectionError is checked before APITimeoutError
-    (its subclass) so timeouts report as connection errors, as they always have.
-    """
+    Errors map to the shared envelope. APIConnectionError is checked before APITimeoutError (its
+    subclass) so timeouts report as connection errors, as they always have."""
     try:
         from openai import OpenAI
         client = OpenAI(api_key=api_key, base_url=base_url, timeout=30, max_retries=0)
@@ -96,13 +94,13 @@ def _transcribe_groq(
 
     def _run(client):
         with open(file_path, "rb") as audio_file:
-            transcription = client.audio.transcriptions.create(
-                file=audio_file, model=model_name, response_format="text", **_sdk_prompt_kwargs(language, prompt))
+            transcription = client.audio.transcriptions.create(file=audio_file, model=model_name,
+                                                               response_format="text",
+                                                               **_sdk_prompt_kwargs(language, prompt))
         transcript_text = str(transcription).strip()
         logger.info("Transcribed %s via Groq API (%s, lang=%s, %d chars)",
                      Path(file_path).name, model_name, language or "auto", len(transcript_text))
         return _ok_result(transcript_text, "groq")
-
     return _with_openai_client(api_key, GROQ_BASE_URL, file_path, "Groq", _run)
 
 
@@ -110,11 +108,9 @@ def _transcribe_openai(
     file_path: str, model_name: str, *, api_key: Optional[str] = None,
     base_url: Optional[str] = None, provider_label: str = "openai", language: Optional[str] = None,
     prompt: Optional[str] = None) -> Dict[str, Any]:
-    """Transcribe via the OpenAI ``audio.transcriptions.create`` SDK shape.
-
-    Shared by every OpenAI-compatible endpoint (DeepInfra etc.): explicit ``api_key``/
-    ``base_url`` skip the OpenAI-only auth chain; ``provider_label`` names the response's provider.
-    """
+    """Transcribe via the OpenAI ``audio.transcriptions.create`` SDK shape, shared by every
+    OpenAI-compatible endpoint (DeepInfra etc.): explicit ``api_key``/``base_url`` skip the
+    OpenAI-only auth chain; ``provider_label`` names the response's provider."""
     from tools.transcription_tools import _HAS_OPENAI, _resolve_openai_audio_client_config, _resolve_stt_language
     if api_key is None:
         try:
@@ -149,7 +145,6 @@ def _transcribe_openai(
                 create_kwargs["prompt"] = prompt
             with open(path, "rb") as audio_file:
                 return client.audio.transcriptions.create(file=audio_file, **create_kwargs)
-
         with tempfile.TemporaryDirectory(prefix="hermes-stt-") as work_dir:
             try:
                 transcription = _create_transcription(file_path)
@@ -167,7 +162,6 @@ def _transcribe_openai(
         logger.info("Transcribed %s via %s (%s, %d chars)",
                     Path(file_path).name, provider_label, model_name, len(transcript_text))
         return _ok_result(transcript_text, provider_label)
-
     return _with_openai_client(api_key, base_url, file_path, provider_label, _run)
 
 
@@ -197,7 +191,6 @@ def _transcribe_mistral(
 
 
 # ---- REST multipart backends (xAI, ElevenLabs) ----------------------------
-
 def _post_audio_multipart(url: str, headers: Dict[str, str], file_path: str, data: Dict[str, str]):
     import requests
     with open(file_path, "rb") as audio_file:
@@ -208,12 +201,10 @@ def _post_audio_multipart(url: str, headers: Dict[str, str], file_path: str, dat
 def _rest_provider(
     file_path: str, provider: str, label: str, post: Callable[[], Any], extract_detail,
     extract_text, log: Callable[[str, Dict[str, Any]], None]) -> Dict[str, Any]:
-    """Shared multipart REST flow: ``post()`` -> ``log(text, body)`` -> ok envelope.
-
-    Non-200 -> ``"<label> API error (HTTP n): detail"`` (JSON detail via *extract_detail*, else
-    the first 300 body chars); empty text -> the ``no_speech`` envelope (silence is non-fatal);
-    exceptions -> ``_cloud_failure``.
-    """
+    """Shared multipart REST flow: ``post()`` -> ``log(text, body)`` -> ok envelope. Non-200 ->
+    ``"<label> API error (HTTP n): detail"`` (JSON detail via *extract_detail*, else the first 300
+    body chars); empty text -> the ``no_speech`` envelope (silence is non-fatal); exceptions ->
+    ``_cloud_failure``."""
     try:
         response = post()
         if response.status_code != 200:
@@ -355,7 +346,6 @@ def _transcribe_deepinfra(
 
 
 # ---- OpenAI audio credential resolution -----------------------------------
-
 def _is_local_or_private_url(url: str) -> bool:
     """True for loopback/RFC-1918/LAN-internal hosts, where an empty ``stt.openai.api_key`` is acceptable
     (local OpenAI-compatible servers ignore the auth header — no sham ``api_key: not-needed`` needed)."""
@@ -404,15 +394,16 @@ def _resolve_openai_audio_client_config() -> tuple[str, str]:
     if selected == NOUS_MANAGED_PROVIDER:
         managed = _managed()
         if managed is None:
-            raise ValueError(selection_error(
-                "stt", NOUS_MANAGED_PROVIDER, "the Nous Tool Gateway is not available (not entitled or unreachable)"))
+            raise ValueError(selection_error("stt", NOUS_MANAGED_PROVIDER,
+                                             "the Nous Tool Gateway is not available (not entitled or unreachable)"))
         return managed
     direct = _direct_openai_credentials(openai_cfg.get("api_key", ""), openai_cfg.get("base_url", ""))
     if direct is not None:
         return direct
     if selected is not None:
         raise ValueError(selection_error(
-            "stt", selected, "neither stt.openai.api_key in config nor VOICE_TOOLS_OPENAI_KEY/OPENAI_API_KEY is set"))
+            "stt", selected,
+            "neither stt.openai.api_key in config nor VOICE_TOOLS_OPENAI_KEY/OPENAI_API_KEY is set"))
     managed = _managed()
     if managed is None:
         message = "Neither stt.openai.api_key in config nor VOICE_TOOLS_OPENAI_KEY/OPENAI_API_KEY is set"
diff --git a/tools/transcription_command.py b/tools/transcription_command.py
index 2bb1ceee53..c0e63a6fe2 100644
--- a/tools/transcription_command.py
+++ b/tools/transcription_command.py
@@ -54,7 +54,8 @@ _get_command_stt_output_format = partial(_command_output_format, formats=COMMAND
 
 def _read_command_stt_output(output_path: Path, stdout: str, fmt: str) -> str:
     """Transcript: non-empty output file > non-empty stdout (curl one-liners) > RuntimeError. JSON is returned raw."""
-    content = output_path.read_bytes().decode("utf-8", errors="replace").strip() if output_path.exists() else ""
+    content = (output_path.read_bytes().decode("utf-8", errors="replace").strip()
+               if output_path.exists() else "")
     if content or (stdout or "").strip():
         return content or stdout.strip()
     raise RuntimeError(f"Command STT provider wrote no output file at {output_path} and produced no stdout")
@@ -64,19 +65,16 @@ def _transcribe_command_stt(
     file_path: str, provider_name: str, config: Dict[str, Any], stt_config: Dict[str, Any],
     model_override: Optional[str] = None, language_override: Optional[str] = None,
     prompt: Optional[str] = None) -> Dict[str, Any]:
-    """Transcribe via a user-declared ``stt.providers.<name>: type: command``.
-
-    Placeholders (shell-quote-aware; ``{{``/``}}`` stay literal): ``{input_path}``,
-    ``{output_path}`` (transcript file), ``{output_dir}``, ``{format}`` txt/json/srt/vtt,
-    ``{language}`` (default ``en``), ``{model}`` (empty when unset).
-    """
+    """Transcribe via a user-declared ``stt.providers.<name>: type: command``. Placeholders
+    (shell-quote-aware; ``{{``/``}}`` stay literal): ``{input_path}``, ``{output_path}`` (transcript
+    file), ``{output_dir}``, ``{format}`` txt/json/srt/vtt, ``{language}`` (default ``en``),
+    ``{model}`` (empty when unset)."""
     from tools.transcription_tools import _resolve_stt_language
     if prompt:
         _log_prompt_unsupported(f"Command STT provider '{provider_name}'")
 
     def fail(error: str) -> Dict[str, Any]:
         return _error_result(error, provider=provider_name)
-
     command_template = str(config.get("command") or "").strip()
     if not command_template:
         return fail(f"stt.providers.{provider_name}.command is not configured")
@@ -128,12 +126,10 @@ def _dispatch_to_plugin_provider(
     model: Optional[str] = None, language: Optional[str] = None, prompt: Optional[str] = None,
 ) -> Optional[Dict[str, Any]]:
     """Route to a plugin-registered transcription provider; None when no plugin claims the name.
-
-    Invariants re-verified here so a caller refactor can't break them: built-in names never
-    reach the registry; a same-name command provider wins over a plugin. A matched plugin with
+    Invariants re-verified here so a caller refactor can't break them: built-in names never reach
+    the registry; a same-name command provider wins over a plugin. A matched plugin with
     ``is_available() == False`` returns an error envelope — not None — because the user
-    explicitly opted in via ``stt.provider``. Provider exceptions become the error envelope.
-    """
+    explicitly opted in via ``stt.provider``. Provider exceptions become the error envelope."""
     key = (provider or "").lower().strip()
     if not key or key in _NON_COMMAND_STT_NAMES:
         return None
@@ -212,12 +208,10 @@ def _apply_pre_transcription_hook(
     prompt: Optional[str], source: Optional[str],
 ) -> tuple[Optional[str], Optional[str], Optional[str]]:
     """Fire the ``pre_transcription`` plugin hook; returns ``(model, language_override, prompt)``.
-
-    Gated on ``has_hook`` (the no-hook path never builds kwargs) and fail-open: any
-    plumbing error leaves the dispatch untouched. Results apply field-by-field in
-    registration order (last hook wins). ``language_override`` is None unless a hook
-    explicitly set ``language``, so backends keep their own config/env resolution.
-    """
+    Gated on ``has_hook`` (the no-hook path never builds kwargs) and fail-open: any plumbing error
+    leaves the dispatch untouched. Results apply field-by-field in registration order (last hook
+    wins). ``language_override`` is None unless a hook explicitly set ``language``, so backends keep
+    their own config/env resolution."""
     try:
         from hermes_cli.plugins import has_hook, invoke_hook
         if not has_hook("pre_transcription"):
diff --git a/tools/transcription_common.py b/tools/transcription_common.py
index c0fa8d8e38..94db230c20 100644
--- a/tools/transcription_common.py
+++ b/tools/transcription_common.py
@@ -61,10 +61,8 @@ def _ok_result(transcript: str, provider: str) -> Dict[str, Any]:
 
 def _lazy_ensure_quietly(dep: str) -> None:
     """Best-effort ``tools.lazy_deps.ensure(dep, prompt=False)``; failures are swallowed.
-
-    prompt=False: a bare input() deadlocks under the interactive CLI where
-    prompt_toolkit owns stdin; installs are gated by ``security.allow_lazy_installs``.
-    """
+    prompt=False: a bare input() deadlocks under the interactive CLI where prompt_toolkit owns
+    stdin; installs are gated by ``security.allow_lazy_installs``."""
     try:
         from tools.lazy_deps import ensure
         ensure(dep, prompt=False)
diff --git a/tools/transcription_local.py b/tools/transcription_local.py
index 78a5aef6bd..515d391f28 100644
--- a/tools/transcription_local.py
+++ b/tools/transcription_local.py
@@ -121,13 +121,10 @@ def _get_idle_unload_seconds(local_cfg: Dict[str, Any]) -> int:
 
 
 def _load_local_whisper_model(model_name: str, device: str = "auto", compute_type: str = "auto"):
-    """Load faster-whisper with graceful CUDA → CPU fallback.
-
-    ``device="auto"`` picks CUDA whenever the ctranslate2 wheel ships CUDA libs, even
-    on hosts without the NVIDIA runtime (WSL2, headless servers). Try the requested
-    config first; on a CUDA library load failure fall back to CPU + int8. Pass
-    ``stt.local.device`` / ``compute_type`` to pin.
-    """
+    """Load faster-whisper with graceful CUDA → CPU fallback. ``device="auto"`` picks CUDA
+    whenever the ctranslate2 wheel ships CUDA libs, even on hosts without the NVIDIA runtime (WSL2,
+    headless servers): try the requested config first; on a CUDA library load failure fall back to
+    CPU + int8. Pass ``stt.local.device`` / ``compute_type`` to pin."""
     force_cpu = _should_force_faster_whisper_cpu()
     if force_cpu:
         # Importing ctranslate2 can itself abort on Apple Silicon/Rosetta when
@@ -194,11 +191,9 @@ def _confidence_thresholds(local_cfg: Dict[str, Any]) -> tuple[float, float]:
 
 
 def _is_hallucinated_segment(segment: Any, no_speech_threshold: float, logprob_threshold: float) -> bool:
-    """True when a segment is very likely a silence hallucination.
-
-    Conservative AND gate (openai-whisper's own heuristic): non-speech AND low decode
-    confidence, so quiet-but-real speech survives. Unknown segment shapes are never dropped.
-    """
+    """True when a segment is very likely a silence hallucination. Conservative AND gate
+    (openai-whisper's own heuristic): non-speech AND low decode confidence, so quiet-but-real speech
+    survives. Unknown segment shapes are never dropped."""
     try:
         return (float(segment.no_speech_prob) > no_speech_threshold
                 and float(segment.avg_logprob) < logprob_threshold)
@@ -227,7 +222,6 @@ def _transcribe_local_command(
     from tools.transcription_tools import _prepare_local_audio, _resolve_stt_language
     if prompt:
         _log_prompt_unsupported("STT provider 'local_command'")
-
     command_template = _get_local_command_template()
     if not command_template:
         return _error_result(f"{LOCAL_STT_COMMAND_ENV} not configured and no local whisper binary was found")
diff --git a/tools/transcription_tools.py b/tools/transcription_tools.py
index 5f697ef3d7..082fe8389c 100644
--- a/tools/transcription_tools.py
+++ b/tools/transcription_tools.py
@@ -104,7 +104,6 @@ _IDLE_UNLOAD_CHECK_INTERVAL = 30  # seconds between idle checks
 
 
 # ---- Config helpers -----------------------------------------------------
-
 def _load_stt_config() -> dict:
     """Load the ``stt`` section from user config, falling back to defaults."""
     try:
@@ -122,11 +121,9 @@ def is_stt_enabled(stt_config: Optional[dict] = None) -> bool:
 def _resolve_stt_language(
     provider_key: str, stt_config: Optional[Dict[str, Any]] = None, *, extra_keys: tuple = ()
 ) -> Optional[str]:
-    """Language hint for an STT provider, first non-empty wins (never "").
-
-    ``stt.<provider>.language`` (plus *extra_keys* aliases, e.g. ``language_code``) >
-    ``stt.language`` > ``HERMES_LOCAL_STT_LANGUAGE`` env > None (provider auto-detects).
-    """
+    """Language hint for an STT provider, first non-empty wins (never ""): ``stt.<provider>.language``
+    (plus *extra_keys* aliases, e.g. ``language_code``) > ``stt.language`` > ``HERMES_LOCAL_STT_LANGUAGE``
+    env > None (provider auto-detects)."""
     if stt_config is None:
         stt_config = _load_stt_config()
     provider_cfg = _get_stt_section(stt_config, provider_key)
@@ -156,7 +153,6 @@ def _is_local_stt_provider(provider: str, stt_config: Dict[str, Any]) -> bool:
 
 
 # ---- Provider resolution ------------------------------------------------
-
 def _has_key(env_var: str, provider: str, *, needs_openai: bool = False, needs_mistral: bool = False):
     """Availability probe factory: optional SDK flag AND a resolvable API key."""
     def probe() -> bool:
@@ -293,7 +289,6 @@ def _get_provider(stt_config: dict) -> str:
 
 
 # ---- Provider: local (faster-whisper) -----------------------------------
-
 def _unload_local_model() -> None:
     """Release the cached local whisper model. Thread-safe via the model lock."""
     global _local_model, _local_model_name
@@ -305,13 +300,10 @@ def _unload_local_model() -> None:
 
 
 def _start_idle_unload_watcher(timeout_seconds: int) -> None:
-    """Ensure the single idle-unload watcher thread is running.
-
-    The loop re-reads ``stt.local.unload_after_idle_seconds`` every cycle so config edits
-    apply within one interval; ``timeout_seconds`` seeds the first cycle so a just-written
-    config is honored even if a concurrent read races. The thread exits after unloading,
-    when the timeout becomes 0, or when the model is already gone.
-    """
+    """Ensure the single idle-unload watcher thread is running. The loop re-reads
+    ``stt.local.unload_after_idle_seconds`` every cycle so config edits apply within one interval;
+    ``timeout_seconds`` seeds the first cycle so a just-written config is honored even if a
+    concurrent read races. Exits after unloading, when the timeout becomes 0, or when the model is gone."""
     global _idle_unload_thread
     with _idle_unload_mgmt_lock:
         if _idle_unload_thread is not None and _idle_unload_thread.is_alive():
@@ -328,7 +320,6 @@ def _start_idle_unload_watcher(timeout_seconds: int) -> None:
                 if time.monotonic() - _last_transcription_time >= timeout:
                     _unload_local_model()
                     break
-
         _idle_unload_stop.clear()
         _idle_unload_thread = threading.Thread(target=_watch, name="hermes-stt-idle-unload", daemon=True)
         _idle_unload_thread.start()
@@ -341,10 +332,8 @@ def _touch_transcription_time() -> None:
 
 
 def _get_or_load_local_model(model_name: str, local_cfg: Dict[str, Any]):
-    """Cached faster-whisper model, (re)loaded under a double-checked lock when needed.
-
-    The returned strong reference stays valid even if the idle watcher nulls the global mid-transcription.
-    """
+    """Cached faster-whisper model, (re)loaded under a double-checked lock when needed. The returned
+    strong reference stays valid even if the idle watcher nulls the global mid-transcription."""
     global _local_model, _local_model_name
     model = _local_model
     if model is None or _local_model_name != model_name:
@@ -385,7 +374,8 @@ def _transcribe_local(
             return _error_result("Local whisper model failed to load")
         # pre_transcription hook overrides win over config-resolved values.
         transcribe_kwargs = build_local_transcribe_kwargs(stt_config)
-        transcribe_kwargs.update({k: v for k, v in (("language", language), ("initial_prompt", prompt)) if v})
+        transcribe_kwargs.update({k: v for k, v in (("language", language), ("initial_prompt", prompt))
+                                  if v})
         try:
             segments, info = model.transcribe(file_path, **transcribe_kwargs)
         except Exception as exc:
@@ -411,7 +401,6 @@ def _transcribe_local(
 
 
 # ---- Public API ---------------------------------------------------------
-
 def _read_block_error(file_path: str) -> Optional[Dict[str, Any]]:
     """Refuse to ship a credential store (auth.json, .env, OAuth tokens) to an STT provider.
     Mirrors the image-gen / video-gen read guards."""
@@ -422,11 +411,9 @@ def _read_block_error(file_path: str) -> Optional[Dict[str, Any]]:
 
 def _transcribe_prepared_audio(
     file_path: str, model: Optional[str] = None, source: Optional[str] = None) -> Dict[str, Any]:
-    """Transcribe a validated audio file with the configured STT provider.
-
-    ``model`` overrides the config default; ``source`` is a caller-surface label
-    (``"gateway"``, ``"voice_mode"``) forwarded to the ``pre_transcription`` hook only.
-    """
+    """Transcribe a validated audio file with the configured STT provider. ``model`` overrides the
+    config default; ``source`` is a caller-surface label (``"gateway"``, ``"voice_mode"``) forwarded
+    to the ``pre_transcription`` hook only."""
     # Validate before provider resolution so invalid files can't trigger provider setup
     # or lazy installation; the remote-upload size cap applies to non-local only.
     error = _read_block_error(file_path) or _validate_audio_file(file_path, enforce_size_limit=False)
@@ -536,11 +523,8 @@ def _no_provider_error(provider: str, stt_config: Dict[str, Any]) -> Dict[str, A
 
 def transcribe_audio(
     file_path: str, model: Optional[str] = None, source: Optional[str] = None) -> Dict[str, Any]:
-    """Validate, preprocess supported inputs, and dispatch transcription.
-
-    ``source`` is a caller-surface label (``"gateway"``, ``"voice_mode"``) forwarded to
-    the ``pre_transcription`` hook for observability only.
-    """
+    """Validate, preprocess supported inputs, and dispatch transcription. ``source`` is a caller-surface
+    label (``"gateway"``, ``"voice_mode"``) forwarded to the ``pre_transcription`` hook only."""
     # Secret-store refusal runs before ANY validation so the error names the real reason.
     blocked = _read_block_error(file_path)
     if blocked:
@@ -563,11 +547,8 @@ def transcribe_audio(
 
 
 def transcribe_audio_local_fallback(file_path: str, model: Optional[str] = None) -> Dict[str, Any]:
-    """Try an already-installed local STT backend without changing config.
-
-    Passive inbound-media recovery after the configured provider failed: never
-    lazy-installs or falls through to a cloud provider.
-    """
+    """Try an already-installed local STT backend without changing config: passive inbound-media
+    recovery after the configured provider failed — never lazy-installs or falls through to cloud."""
     error = _validate_audio_file(file_path)
     if error:
         return error
diff --git a/tools/tts_command_provider.py b/tools/tts_command_provider.py
index 5a636dc3bd..c5c6f412d3 100644
--- a/tools/tts_command_provider.py
+++ b/tools/tts_command_provider.py
@@ -111,7 +111,8 @@ def terminate_command_process_tree(proc: subprocess.Popen) -> None:
     except ImportError:
         psutil = None
     # Without psutil only the shell itself is signalled (children may survive).
-    signal = (lambda m: getattr(proc, m)()) if psutil is None else (lambda m: _signal_process_tree(psutil, proc, m))
+    signal = ((lambda m: getattr(proc, m)()) if psutil is None
+              else (lambda m: _signal_process_tree(psutil, proc, m)))
     signal("terminate")
     try:
         proc.wait(timeout=2)
@@ -122,7 +123,7 @@ def terminate_command_process_tree(proc: subprocess.Popen) -> None:
 def command_env_passthrough(config: Dict[str, Any]) -> list:
     """``env_passthrough`` allowlist: parent env vars copied back into the secret-scrubbed child env."""
     raw = config.get("env_passthrough")
-    return [str(item).strip() for item in raw if str(item).strip()] if isinstance(raw, (list, tuple)) else []
+    return [str(x).strip() for x in raw if str(x).strip()] if isinstance(raw, (list, tuple)) else []
 
 
 def command_failure_detail(exc: subprocess.CalledProcessError) -> str:
@@ -211,7 +212,6 @@ def run_command_provider(
 
 
 # ---- Generic ``<section>.providers.<name>`` config layer (TTS and STT share it) ----
-
 def _get_provider_section(config: Dict[str, Any], name: str) -> Dict[str, Any]:
     """Return ``config[name]`` if it's a dict, else an empty dict."""
     section = config.get(name) if isinstance(config, dict) else None
@@ -219,8 +219,8 @@ def _get_provider_section(config: Dict[str, Any], name: str) -> Dict[str, Any]:
 
 
 def _named_provider_config(config: Dict[str, Any], name: str, builtins: FrozenSet[str]) -> Dict[str, Any]:
-    """``<section>.providers.<name>`` (canonical), else ``<section>.<name>`` for non-built-in names only —
-    refused for built-ins so a user's ``openai:`` block still means the OpenAI provider, not a command."""
+    """``<section>.providers.<name>`` (canonical), else ``<section>.<name>`` for non-built-in names
+    only — refused for built-ins so a user's ``openai:`` block still means OpenAI, not a command."""
     section = _get_provider_section(config, "providers").get(name)
     if isinstance(section, dict):
         return section
@@ -310,7 +310,7 @@ def _generate_command_tts(
     text: str, output_path: str, provider_name: str, config: Dict[str, Any], tts_config: Dict[str, Any],
 ) -> str:
     """Generate speech by running a user-configured shell command; returns the audio path it wrote.
-    Raises ``ValueError`` for invalid provider config, ``RuntimeError`` for timeouts / non-zero exits / empty output."""
+    Raises ``ValueError`` for bad provider config, ``RuntimeError`` for timeouts / bad exits / no output."""
     command_template = str(config.get("command") or "").strip()
     if not command_template:
         raise ValueError(f"tts.providers.{provider_name}.command is not configured")
@@ -324,8 +324,9 @@ def _generate_command_tts(
         text_path.write_text(text, encoding="utf-8")
         placeholders = {
             "input_path": str(text_path), "text_path": str(text_path), "output_path": str(output),
-            "format": _get_command_tts_output_format(config, str(output)), "voice": str(config.get("voice", "")),
-            "model": str(config.get("model", "")), "speed": str(config.get("speed", tts_config.get("speed", ""))),
+            "format": _get_command_tts_output_format(config, str(output)),
+            "voice": str(config.get("voice", "")), "model": str(config.get("model", "")),
+            "speed": str(config.get("speed", tts_config.get("speed", ""))),
         }
         command = render_command_template(command_template, placeholders)
         try:
diff --git a/tools/tts_streaming.py b/tools/tts_streaming.py
index f3f44029d2..5447cf272d 100644
--- a/tools/tts_streaming.py
+++ b/tools/tts_streaming.py
@@ -96,7 +96,7 @@ class SentenceChunker:
 
 
 class StreamingTTSProvider(ABC):
-    """Yields raw int16, little-endian, mono PCM chunks at ``sample_rate`` (built-in streamers: 24 kHz)."""
+    """Yields raw int16, little-endian, mono PCM chunks at ``sample_rate`` (built-ins: 24 kHz)."""
 
     sample_rate: int = 24000
     channels: int = 1
@@ -153,7 +153,8 @@ def resolve_streaming_provider(
     providers just to get streaming."""
     pinned = str((tts_config.get("streaming") or {}).get("provider") or "").lower().strip()
     if pinned == "auto":
-        return next((inst for name in _PROVIDER_PRIORITY if (inst := _try_instantiate(name, tts_config))), None)
+        return next((inst for name in _PROVIDER_PRIORITY
+                     if (inst := _try_instantiate(name, tts_config))), None)
     return _try_instantiate(pinned or (preferred or _get_provider(tts_config)).lower().strip(), tts_config)
 
 
@@ -274,7 +275,8 @@ class GeminiStreamer(StreamingTTSProvider):
 class XAIStreamer(StreamingTTSProvider):
     """xAI WebSocket TTS (``wss://api.x.ai/v1/tts``) → binary PCM frames (24 kHz mono int16).
     Credentials route through ``resolve_xai_http_credentials`` (OAuth or XAI_API_KEY), same as the
-    sync path. ``_collect_async`` bridges the async WS loop to the sync iterator contract (test seam)."""
+    sync path. ``_collect_async`` bridges the async WS loop to the sync iterator contract (test
+    seam)."""
 
     @staticmethod
     def available() -> bool: