Interim results

Interim results provide partial transcripts while the speaker is still talking. The transcript updates progressively as more audio arrives, giving your application low-latency feedback before a sentence is finalized.

Usage

Interim results are enabled by default. To disable them and receive only final transcripts, set interim_results=false in the WebSocket query string:

# Default (interim results enabled)
wss://api.aldea.ai/v1/listen?encoding=mp3

# Disable interim results
wss://api.aldea.ai/v1/listen?encoding=mp3&interim_results=false

How it works

As audio streams in, the server sends Results messages. Each message contains two key fields:

A typical sequence looks like:

1. is_final: false returns "Hello"
2. is_final: false returns "Hello world"
3. is_final: true returns "Hello world, how are you?"
4. speech_final: true signals utterance complete

Interim results let you display text as the user speaks (like live captions), while final results give you the stable transcript to store or process.

Example response

{
  "type": "Results",
  "is_final": false,
  "speech_final": false,
  "channel": {
    "alternatives": [{
      "transcript": "Hello world",
      "confidence": 0.95
    }]
  }
}

Next steps

• Endpointing to control when sentences are finalized
• Utterance detection to detect end of speaker turns
• WebSocket protocol for the full message reference