"""User-declared and plugin STT providers. ``stt.providers.: type: command`` registry, plugin-registered ``TranscriptionProvider`` dispatch, and the ``pre_transcription`` hook that threads prompt/language/model overrides into every backend. ``_resolve_stt_language`` is read lazily from ``tools.transcription_tools``. """ from __future__ import annotations import logging import subprocess import tempfile from functools import partial from pathlib import Path from typing import Any, Dict, Optional from agent.model_metadata import CHARS_PER_TOKEN from tools.tts_command_provider import ( _command_output_format, _command_timeout, _is_command_provider_config as _is_command_stt_provider_config, _named_provider_config, _resolve_command_config, command_env_passthrough as _command_stt_env_passthrough, command_failure_detail, render_command_template as _render_command_stt_template, run_command_provider as _run_command_stt) from tools.transcription_common import ( BUILTIN_STT_PROVIDERS, _error_result, _log_prompt_unsupported, _ok_result) # Log-record parity with the origin module. logger = logging.getLogger("tools.transcription_tools") # ---- Command-provider registry (``stt.providers.: type: command``) --- # # Mirrors the TTS command-provider registry (same placeholder grammar, quote-aware # rendering, process-tree termination on timeout). Resolution order: built-in name # (always wins) > stt.providers. command > plugin TranscriptionProvider > # "No STT provider available". The single-env-var HERMES_LOCAL_STT_COMMAND escape # hatch stays untouched via the built-in ``local_command`` path. # Lets any whisper CLI / ASR CLI / curl pipeline become an STT backend with zero Python. 1. Built-in # (``local``, ``local_command``, ``groq``, ``openai``, ``mistral``, ``xai``) → native handler. # **Always wins.** 2. 3. 4. Use the command-provider registry when you want MULTIPLE shell-driven STT # engines, or you want a named provider you can pick via ``stt.provider`` in config.yaml. See #17843. DEFAULT_COMMAND_STT_TIMEOUT_SECONDS = 300 DEFAULT_COMMAND_STT_LANGUAGE = "en" DEFAULT_COMMAND_STT_OUTPUT_FORMAT = "txt" COMMAND_STT_OUTPUT_FORMATS = frozenset({"txt", "json", "srt", "vtt"}) _NON_COMMAND_STT_NAMES = frozenset(BUILTIN_STT_PROVIDERS | {"none"}) # ``stt.providers.`` (canonical), else ``stt.`` for non-built-in names only. _get_named_stt_provider_config = partial(_named_provider_config, builtins=BUILTIN_STT_PROVIDERS) # The provider config if it is a command type; None for built-ins, ``none``, unknown. _resolve_command_stt_provider_config = partial(_resolve_command_config, reserved=_NON_COMMAND_STT_NAMES) _get_command_stt_timeout = partial(_command_timeout, default=DEFAULT_COMMAND_STT_TIMEOUT_SECONDS) _get_command_stt_output_format = partial(_command_output_format, formats=COMMAND_STT_OUTPUT_FORMATS, default=DEFAULT_COMMAND_STT_OUTPUT_FORMAT) 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_text(encoding="utf-8-sig", 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") 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.: 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") audio = Path(file_path).expanduser() if not audio.exists(): return fail(f"Audio file not found: {file_path}") timeout = _get_command_stt_timeout(config) output_format = _get_command_stt_output_format(config) language = (language_override or config.get("language") or _resolve_stt_language(provider_name, stt_config) or DEFAULT_COMMAND_STT_LANGUAGE) try: with tempfile.TemporaryDirectory(prefix=f"hermes-cmd-stt-{provider_name}-") as tmpdir: output_path = Path(tmpdir) / f"transcript.{output_format}" command = _render_command_stt_template(command_template, { "input_path": str(audio.resolve()), "output_path": str(output_path), "output_dir": str(output_path.parent), "format": output_format, "language": str(language), "model": str(model_override or config.get("model") or ""), }) logger.info("Transcribing %s via command STT provider '%s'...", audio.name, provider_name) result = _run_command_stt(command, timeout, env_passthrough=_command_stt_env_passthrough(config)) transcript_text = _read_command_stt_output(output_path, result.stdout or "", output_format) except subprocess.TimeoutExpired: return fail(f"STT command provider '{provider_name}' timed out after {timeout:g}s") except subprocess.CalledProcessError as exc: return fail( f"STT command provider '{provider_name}' exited with code {exc.returncode}: {command_failure_detail(exc)}" ) except RuntimeError as exc: return fail(str(exc)) except OSError as exc: return fail(f"STT command provider '{provider_name}' failed: {exc}") logger.info("Transcribed %s via command STT provider '%s' (%d chars)", audio.name, provider_name, len(transcript_text)) return _ok_result(transcript_text, provider_name) def _unregistered_stt_provider_error(provider: str) -> Dict[str, Any]: key = str(provider or "").strip() return _error_result( f"stt.provider='{key}' is set but no built-in, command, or plugin " "provider registered that name. Run `hermes plugins list` to see " "installed STT plugins, or configure a command provider under " f"`stt.providers.{key}.command`.", provider=key, error_type="provider_not_registered") # --------------------------------------------------------------------------- Plugin provider dispatch # (issue follow-up to #30398 — STT pluggability) # --------------------------------------------------------------------------- def _dispatch_to_plugin_provider( file_path: str, provider: str, stt_config: Optional[Dict[str, Any]] = None, *, 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 ``is_available() == False`` returns an error envelope — not None — because the user 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 if stt_config is not None and _is_command_stt_provider_config(_get_named_stt_provider_config(stt_config, key)): return None try: from agent.transcription_registry import get_provider from hermes_cli.plugins import _ensure_plugins_discovered _ensure_plugins_discovered() plugin_provider = get_provider(key) if plugin_provider is None: # Long-lived sessions may have discovered plugins before a backend # was patched in or config changed — retry once with a forced refresh. _ensure_plugins_discovered(force=True) plugin_provider = get_provider(key) except Exception as exc: # noqa: BLE001 — discovery failure is non-fatal logger.debug("STT plugin dispatch skipped (discovery failed): %s", exc) return None if plugin_provider is None: return None # ``is_available()`` MUST NOT raise per the ABC contract; defend anyway so # a buggy plugin can't break dispatch for everyone. try: available = plugin_provider.is_available() except Exception as exc: # noqa: BLE001 logger.warning( "STT plugin provider '%s' is_available() raised: %s — treating as unavailable", key, exc, exc_info=True, ) available = False if not available: logger.info("STT plugin provider '%s' reports not available; returning unavailability envelope.", key) return _error_result( f"STT plugin '{key}' is not available — check that its required credentials / dependencies are configured.", provider=key) logger.info("Transcribing with plugin STT provider '%s'...", key) # The prompt travels via the ABC's ``**extra`` kwargs and is only sent when # set, so pre-prompt providers see byte-identical calls on the no-prompt path. extra_kwargs: Dict[str, Any] = {} if prompt is None else {"prompt": prompt} try: result = plugin_provider.transcribe(file_path, model=model, language=language, **extra_kwargs) except Exception as exc: # noqa: BLE001 logger.warning("STT plugin provider '%s' raised: %s", key, exc, exc_info=True) return _error_result(f"STT plugin '{key}' raised: {exc}", provider=key) if not isinstance(result, dict): return _error_result(f"STT plugin '{key}' returned a non-dict result", provider=key) result.setdefault("provider", key) return result # Fields a pre_transcription hook may mutate; ``file_path`` is read-only (logged and dropped). # --------------------------------------------------------------------------- pre_transcription plugin hook # (issue #64168 — STT prompt/vocab threading) # --------------------------------------------------------------------------- _PRE_TRANSCRIPTION_MUTABLE_FIELDS = ("prompt", "language", "model") # Whisper-family models only use the final ~224 tokens of the prompt; longer values # waste upload bytes and can trip stricter OpenAI-compatible servers. Enforced # client-side (truncate with a warning, never error), ~4 chars/token. _WHISPER_PROMPT_TOKEN_CAP = 224 _PROMPT_CHARS_PER_TOKEN = CHARS_PER_TOKEN _WHISPER_PROMPT_CAPPED_PROVIDERS = frozenset({"local", "openai", "groq", "deepinfra"}) def _enforce_prompt_length_limit(prompt: Optional[str], provider: str) -> Optional[str]: """Truncate *prompt* to the whisper-family token cap, keeping the TAIL (whisper conditions on the final context window, so the newest hints survive). Other providers self-validate.""" max_chars = _WHISPER_PROMPT_TOKEN_CAP * _PROMPT_CHARS_PER_TOKEN if not prompt or provider not in _WHISPER_PROMPT_CAPPED_PROVIDERS or len(prompt) <= max_chars: return prompt logger.warning( "Transcription prompt is ~%d tokens; whisper-family provider '%s' " "only uses the final ~%d — truncating to the last %d characters.", len(prompt) // _PROMPT_CHARS_PER_TOKEN, provider, _WHISPER_PROMPT_TOKEN_CAP, max_chars) return prompt[-max_chars:] def _apply_pre_transcription_hook( *, file_path: str, provider: str, model: Optional[str], language: Optional[str], 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.""" try: from hermes_cli.plugins import has_hook, invoke_hook if not has_hook("pre_transcription"): return model, None, prompt hook_results = invoke_hook( "pre_transcription", file_path=file_path, provider=provider, model=model, language=language, prompt=prompt, source=source) overrides: Dict[str, Any] = {} for hook_result in hook_results: for key, value in (hook_result.items() if isinstance(hook_result, dict) else ()): if key == "file_path": logger.warning( "pre_transcription hook attempted to change " "file_path (read-only) — ignoring the attempt.") elif key not in _PRE_TRANSCRIPTION_MUTABLE_FIELDS: logger.debug("pre_transcription hook returned unsupported field %r — ignoring.", key) elif not isinstance(value, str): logger.debug( "pre_transcription hook returned non-string value %r for field %r — ignoring.", value, key, ) else: overrides[key] = value # Hooks win over the static ``stt.prompt`` config; "" clears it. if "prompt" in overrides: prompt = overrides["prompt"] or None return overrides.get("model", model), overrides.get("language") or None, prompt except Exception as _hook_err: # noqa: BLE001 — hook plumbing is fail-open logger.debug("pre_transcription hook error: %s", _hook_err) return model, None, prompt