Multilanguage Input¶

When building custom IO interfaces (beyond the built-in Voice Assistant), you can provide per-word language metadata to the parsing pipeline via TranscriptionString. This metadata is optional — the parser works with plain strings and LocaleString too — but when available, it enables per-parameter language resolution for mixed-language input.

TranscriptionString¶

TranscriptionString extends LocaleString with per-word language annotations:

from stark.models.transcription_string import TranscriptionString

ts = TranscriptionString.from_words([
    ("set", "en"), ("timer", "en"), ("for", "en"),
    ("zwei", "de"), ("часа", "ru"),
])
# ts == "set timer for zwei часа"
# ts.language_code == "en" (majority language)

When the parser slices a parameter substring (e.g., "zwei часа" for a Duration parameter), TranscriptionString automatically resolves the majority language of that span — in this case "de", not "en". The parser then uses the German Duration pattern for matching and passes the correct language to did_parse.

All string operations (slicing, replace, strip, split) preserve the per-word language metadata.

When to Use¶

Use TranscriptionString when your input source provides per-word language information:

STT engines that tag each word with its detected language
NLP pipelines that perform language identification per token
Translation APIs that return source language annotations
Manual annotation for testing multilingual commands

For single-language input, plain LocaleString is sufficient.

Alternative Tracks¶

TranscriptionString can carry alternative_texts — the same utterance as processed by different language models:

from stark.general.localisation import LocaleString

ts = TranscriptionString.from_words(
    [("set", "en"), ("timer", "en")],
    alternative_texts={
        "ru": LocaleString("сет таймер", "ru"),
        "de": LocaleString("set timer", "de"),
    },
)

When STARK_ENABLE_MULTILANG_MATRIX=1 (default), the parser tries each alternative track against its language's command patterns concurrently, merging results. This catches commands that exist only in specific languages.

VoiceTranscriptionString¶

For voice input, VoiceTranscriptionString extends TranscriptionString with time-aligned audio metadata:

from stark.models.voice_transcription_string import VoiceTranscriptionString

This adds per-word timestamps, confidence scores, and speaker embeddings. This data is used by the parser to resolve overlapping matches across alternative tracks, set priorities, improve recognition accuracy. Speaker identification is not used yet, but this is something to be added in the future.

See Voice Assistant for the built-in multi-STT setup that produces VoiceTranscriptionString automatically.

Passing to the Parser¶

Pass TranscriptionString (or any LocaleString subclass) directly to process_string:

await context.process_string(ts)

The parser handles it as a regular string — TranscriptionString is a str subclass. The metadata enhances pattern resolution without requiring any changes to your commands or types.

See Feature Flags for additional configuration options like tweaking multilingual features.