# Smallest.ai Pulse STT (slim)

> Smallest AI's Pulse speech-to-text API transcribes pre-recorded files over HTTP and live audio over WebSocket, with three models (Pulse, Pulse 2.0 and Pulse Pro), diarisation, word timestamps, redaction and turn detection.

- Full: https://www.anchorterminal.com/tools/smallest-pulse-stt.md (~8,400 tokens) · this version ~1,780 tokens · JSON https://www.anchorterminal.com/tools/smallest-pulse-stt.json · canonical https://www.anchorterminal.com/tools/smallest-pulse-stt
- Index: https://www.anchorterminal.com/llms.txt · API: https://www.anchorterminal.com/api/v1/index.json · MCP: https://www.anchorterminal.com/mcp · Updated: 2026-11-07 · pricing https://www.anchorterminal.com/tools/smallest-pulse-stt#pricing · reviews https://www.anchorterminal.com/tools/smallest-pulse-stt#reviews
- Licence: CC BY 4.0, credit Anchor Terminal and link this page (https://www.anchorterminal.com/terms/#data)

**B · 65/100 · rank #441 of 1486 · #13 in Speech-to-text · not agent-ready · confidence medium**


Assessment: Pulse covers files and live audio on one endpoint, with OpenAPI and AsyncAPI files, a dated changelog and public per-minute prices from $0.003. The shared API's health checks failed in every region on five days in September, keys carry no scopes and can travel in a URL, and zero retention is Enterprise only.

## Facts

- Kind: Model API · vendor: Smallest AI · category: Speech-to-text · legal entity: Smallest, Inc. · provenance 87/100
- Local only (HTTP, websocket): pypi `smallestai`, npm `smallestai`, npm `@developer-smallestai/smallest-mcp-server`
- Auth: API key · pricing: Pay per use · x402: no · licence: unknown
- Benchmark probes: not run yet, so Performance is pending
- Vendor status page: not read, no machine-readable status found (2026-11-07 04:48 UTC)
- Surface listed: The Pulse speech-to-text routes of the Models API at api.smallest.ai/waves/v1, read from docs.smallest.ai (Markdown pages, llms.txt, OpenAPI and AsyncAPI files, changelog), smallest.ai pricing, terms and privacy pages and status.smallest.ai on 6 November 2026. No account was made and no request was sent to the API
- Models: `pulse` (multilingual, streaming and batch), `pulse-2` (English streaming with end-of-turn, emotion and gender) and `pulse-pro` (English batch only, which the vendor says is tied second on the Open ASR Leaderboard at 5.42% WER)
- Languages: Streaming takes 21 single-language codes plus `north_indic`, `multi-asian` and `multi-south-indic`. Batch takes 12 codes plus `multi-eu`, `multi-asian` and `multi-indic`. Eleven languages are labelled Beta, and East Asian streaming runs from the US region
- Options: Word timestamps, utterances, diarisation with integer speaker labels, PII and PCI redaction (Pulse only), keyword boosting up to 100 terms, emotion and gender detection, inverse text normalisation, VAD events and webhooks for batch results
- Regions: Mumbai and Oregon, routed by proximity, with region-pinned hosts api.india.smallest.ai and api.us.smallest.ai
- MCP server: `@developer-smallestai/smallest-mcp-server` 0.11.2 (MIT, npm) runs locally with npx and mostly manages voice agents, with a `transcribe_audio` tool among about 80
- Other products: Lightning text to speech (listed separately), Hydra speech to speech, the Electron LLM, voice cloning and the Atoms voice agent platform share the same key and quota
- SDKs: Python `smallestai` 5.14.0 (7 October 2026). The npm `smallestai` Node SDK is at 1.0.1, last published in May 2025
- Prices: Pulse pre-recorded $0.003 per minute of audio; Pulse streaming $0.004 per minute of audio; Pulse Pro pre-recorded $0.0035 per minute of audio; Pulse 2.0 streaming $0.005 per minute of audio

- Scores: Reliability 63, Performance pending, Schema & documentation 92, Agent ergonomics 66, Security & auth 52, Payments & pricing 40, Task success pending, Maintenance & community 73, Transparency & trust 71 · total over the 7 assessed categories
- Why: Reliability, BetterStack status page at status.smallest.ai with components for the Global, India and USA APIs (one health check covers the Agents and Mod… · Schema & documentation, OpenAPI 3.1 for the HTTP routes and AsyncAPI 2.6 for the STT socket, with query parameters and event schemas (25). · Agent ergonomics, API reading of the checklist. · Security & auth, Model reading of the checklist, with training and retention in place of the least-privilege and injection lines. · Payments & pricing, No x402, MPP or L402 (0). · Maintenance & community, Read as a model. · Transparency & trust, Closed service with clear terms naming Smallest Inc.
- Sources: 18, open questions: 5, both in the full twin
- Capabilities: speech.stt, speech.streaming, speech.batch, speech.diarisation, speech.languages
- JSON: https://www.anchorterminal.com/api/v1/tools/smallest-pulse-stt.json
- Verify (for the vendor): the badge `https://www.anchorterminal.com/badges/smallest-pulse-stt.svg` or a link to https://www.anchorterminal.com/tools/smallest-pulse-stt from a page on smallest.ai or one of its subdomains, or the README at the root of github.com/smallest-inc/smallest-python-sdk, then `POST https://www.anchorterminal.com/api/v1/verify` `{"slug", "url"}` or `verify_listing` at /mcp; re-checked weekly, no effect on the grade. Snippets in the full twin.
- Support: Discord https://discord.com/invite/xNBrdjdBa6; support@smallest.ai; https://docs.smallest.ai/voice-agents/resources/getting-help; https://status.smallest.ai/; more in the full twin

## Before you call it

1. Pass `?model=` on every call, since a missing model returns 400; use `pulse-pro` for English files and `pulse` for other languages or streaming
2. Send booleans such as `diarize` and `word_timestamps` as the lowercase strings "true" or "false"
3. Retry 429 with backoff from 500 ms up to 30 s and honour Retry-After; keep within 25 batch requests a minute on the Standard plan
4. Use the region-pinned host api.us.smallest.ai or api.india.smallest.ai when the audio must stay in one region
5. Read speaker labels only from final events, because interim streaming events carry no `words[]`

## Connect

```bash
pip install smallestai
```

```bash
curl -X POST "https://api.smallest.ai/waves/v1/stt/?model=pulse&language=en" \
  -H "Authorization: Bearer $SMALLEST_API_KEY" -H "Content-Type: application/json" \
  -d '{"url": "https://github.com/smallest-inc/cookbook/raw/main/speech-to-text/getting-started/samples/audio.wav"}'
```

```bash
claude mcp add smallest -- npx -y @developer-smallestai/smallest-mcp-server
```

## Similar tools

| Tool | Grade | Score | Shared capabilities | Slim |
| --- | --- | --- | --- | --- |
| Azure AI Speech speech-to-text | BB | 75.1 | speech.stt, speech.streaming, speech.batch, speech.diarisation, speech.languages | https://www.anchorterminal.com/tools/azure-speech-to-text.min.md |
| OpenAI Speech to Text | BB | 75 | speech.stt, speech.streaming, speech.batch, speech.diarisation, speech.languages | https://www.anchorterminal.com/tools/openai-speech-to-text.min.md |
| Deepgram Speech-to-Text (Nova-3, Flux) | BB | 74.4 | speech.stt, speech.streaming, speech.batch, speech.diarisation, speech.languages | https://www.anchorterminal.com/tools/deepgram-stt.min.md |
| Amazon Transcribe | BB | 73.6 | speech.stt, speech.streaming, speech.batch, speech.diarisation, speech.languages | https://www.anchorterminal.com/tools/amazon-transcribe.min.md |
| ElevenLabs Scribe Speech to Text API | BB | 73 | speech.stt, speech.streaming, speech.batch, speech.diarisation, speech.languages | https://www.anchorterminal.com/tools/elevenlabs-scribe.min.md |


## Panel reviews (0, desk reviews from public material, no calls made)