SDKs

Official client SDKs are available for Python and TypeScript/Node. Both cover the full API: instant and demand streaming over the /audio/v1/listen WebSocket, whole-file transcription over POST /audio/v1/transcribe, PII redaction, keyword boosting, word timestamps, and transcript assembly helpers. Source, full guides, and runnable examples live in the bw_labs_sdks repository. During the beta the SDKs are installed straight from that repository; package registry releases come later.

Create an API key from your dashboard and set it as BW_STT_API_KEY in your environment; both SDKs pick it up automatically.

Install

Clone the repository, then install the SDK for your language from its folder.

git clone https://github.com/Bandwidth/bw_labs_sdks.git

Python, into your project's environment:

pip install ./bw_labs_sdks/python

TypeScript/Node, build once and add the folder to your project:

cd bw_labs_sdks/typescript && npm install && cd -
npm install ./bw_labs_sdks/typescript

Live transcription (instant mode)

Stream audio and print words as they land. Segments are final the moment they arrive; the assembler joins them into a running transcript.

from bw_stt import BwSttClient, TranscriptAssembler

client = BwSttClient()
transcript = TranscriptAssembler()
with client.connect(encoding="linear16", sample_rate=16000) as session:
    session.on_segment(transcript.push)
    for _segment in session.stream_file("call.wav"):
        print("\r" + transcript.text, end="", flush=True)
    closed = session.close_stream()
print("\r" + transcript.text)

import { BwSttClient } from "@bandwidth/bw-stt";

const client = new BwSttClient();
const session = await client.connect({ encoding: "linear16", sampleRate: 16000 });
session.on("segment", (segment) => process.stdout.write(segment.text));
for await (const segment of session.streamFile("call.wav")) void segment;
await session.closeStream();

Transcripts on your schedule (demand mode)

In demand mode nothing is delivered until you ask. Stream audio, then call the finalize helper at each boundary you care about, such as the end of a caller turn. Each call returns one finalized transcript per channel.

with client.connect(mode="demand") as session:
    session.send_audio(turn_audio)
    transcripts = session.finalize_transcript()  # one Transcript per channel
    print(transcripts[0].text)

const session = await client.connect({ mode: "demand" });
session.sendAudio(turnAudio);
const transcripts = await session.finalizeTranscript();
console.log(transcripts[0].text);

Whole recordings (Transcribe)

One call for a complete recording of up to five minutes. The result carries the full text, word timestamps, and segments.

result = client.transcribe("call.wav")
print(result.text)
for word in result.words[:5]:
    print(word.word, word.start, word.end)

import { readFile } from "node:fs/promises";

const result = await client.transcribe(await readFile("call.wav"));
console.log(result.text);

Redaction and keywords

Both SDKs expose the PII and keyword options as typed parameters on connect and transcribe. Redaction is available in demand and Transcribe modes.

result = client.transcribe(
    "call.wav",
    redact_pii=True,
    redact_pii_return=True,
    keywords=["Bandwidth", "porting"],
)
for entity in result.redacted_entities:
    print(entity.kind, entity.token, entity.text)

const result = await client.transcribe(audio, {
  redactPii: true,
  redactPiiReturn: true,
  keywords: ["Bandwidth", "porting"],
});

For event handling, error taxonomy, browser usage, codec options, and complete examples, see the language guides in the repository.