API ReferenceMultimodal

Speech to text

Transcribe audio to text through the Respan gateway with automatic logging.

Authentication

AuthorizationBearer
Use your Respan API key for Respan API authentication. Enter only the Respan API key value; clients send Authorization: Bearer <RESPAN_API_KEY>. For /api/responses, provider credentials such as Perplexity, OpenAI, or Azure OpenAI go in Settings -> Providers or respan_params.credential_override in the request body, not in this authentication field.

Headers

X-Data-Respan-ParamsstringOptional

Base64-encoded JSON object of Respan parameters. Legacy X-Data-Keywordsai-Params is still accepted.

Request

This endpoint expects a multipart form containing a file.
filefileRequired

Audio file. Supported: flac, mp3, mp4, mpeg, mpga, m4a, ogg, wav, webm.

modelenumRequired
Model ID.
Allowed values:
languagestringOptional

Input audio language (ISO-639-1).

promptstringOptional
Optional text to guide the model's style.
response_formatenumOptionalDefaults to json
Output format.
Allowed values:
temperaturedoubleOptional

Sampling temperature (0-1).

timestamp_granularitieslist of enumsOptional

Timestamp granularities. Requires verbose_json response format.

Allowed values:
customer_credentialsobjectOptional

Per-customer LLM provider credentials.

disable_logbooleanOptionalDefaults to false

When true, omits input/output from the log. Metrics still recorded.

metadataobjectOptional

Custom key-value metadata.

customer_identifierstringOptional
End user identifier.
thread_identifierstringOptional
Conversation thread ID.

Response

Transcription result.
textstringOptional
Transcribed text.
languagestringOptional
Detected language.
durationdoubleOptional
Audio duration in seconds.
wordslist of objectsOptional

Word-level timestamps (if requested).

segmentslist of objectsOptional

Segment-level timestamps (if requested).

Errors

401
Unauthorized Error