- provider_registry.py: ProviderRegistry (global + per-scope maps, lock,
generation counters, register/list/get/snapshot/restore/reset) with
export() binding the historical module-level names and _providers/
_scoped_providers/_lock test hooks into each *_registry module
- is_available_safe / configured_provider_name replace the 4 nested
_is_available_safe closures and 2 config-reading blocks
- browser/image_gen/video_gen/web_search/terminal_env/tts/transcription
registries keep their public API, log strings, error strings, builtin
collision policy (warn vs raise) and key normalization (strip vs lower)
Add an opt-in Python plugin surface for speech-to-text backends,
mirroring the TTS hook pattern. New backends (OpenRouter, SenseAudio,
Gemini-STT, custom proprietary engines) can be implemented as plugins
without modifying tools/transcription_tools.py.
Built-ins always win
--------------------
The 6 built-in STT providers (local/faster-whisper, local_command,
groq, openai, mistral, xai) keep their native handlers. Plugins
attempting to register under a built-in name are rejected at
registration time with a warning and re-checked defensively at
dispatch.
Resolution order
----------------
1. stt.provider matches a built-in → built-in dispatch (unchanged)
2. stt.provider matches a registered plugin →
a. if plugin.is_available() returns False → unavailability envelope
identifying the plugin (not the generic "No STT provider"
message — the user explicitly opted into this plugin)
b. otherwise plugin.transcribe() with model + language forwarded
from stt.<provider>.{model,language} config
3. No match → legacy "No STT provider available" error (unchanged)
Per-provider config namespace
-----------------------------
Plugins read their config from stt.<provider> in config.yaml, mirroring
how built-ins read stt.openai.model / stt.mistral.model. The dispatcher
forwards `model` and `language` from this section. Caller's explicit
`model=` argument overrides the config-set model.
Files
-----
- agent/transcription_provider.py: TranscriptionProvider ABC
- agent/transcription_registry.py: register/get/list providers,
built-in shadow guard, _reset_for_tests
- hermes_cli/plugins.py: register_transcription_provider() on
PluginContext
- tools/transcription_tools.py: BUILTIN_STT_PROVIDERS frozenset,
_dispatch_to_plugin_provider() with availability gate, wire-in
after xai branch and before "No STT provider" error
- tests/agent/test_transcription_registry.py: 27 tests
- tests/hermes_cli/test_plugins_transcription_registration.py: 3 tests
- tests/tools/test_transcription_plugin_dispatch.py: 28 tests
(covering built-in short-circuit, plugin dispatch, exception
envelope, non-dict guard, availability gate, language forwarding)
- tests/plugins/transcription/check_parity_vs_main.py: 10-scenario
subprocess-pinned parity harness vs origin/main
- website/docs/user-guide/features/{tts,plugins}.md: docs
Behavior parity
---------------
10 scenarios, 8 OK + 2 expected DIFFs:
no_provider_error → plugin (plugin-installed scenario)
no_provider_error → plugin_unavailable (plugin-installed-unavailable
scenario; PR returns cleaner envelope)
Zero behavior change for users not opting into a plugin.
Issue follow-up to #30398.
Teknium