API Documentation

Signal Loom AI API — transcription and cost intelligence endpoints.

Signal Loom AI API

Base URL: https://api.signalloomai.com

Authentication

All requests require an API key:

Authorization: Bearer <your_api_key>

Get your free API key →


Transcription

POST /v1/transcribe

Transcribe an audio file and receive structured JSON, SRT, and VTT output.

curl -X POST https://api.signalloomai.com/v1/transcribe \
  -H "Authorization: Bearer $SL_API_KEY" \
  -F "file=@recording.mp3" \
  -F "output_formats=json,srt,vtt" \
  -F "word_timestamps=true"

Response:

{
  "job_id": "slj_01HX...",
  "status": "completed",
  "formats": {
    "json": "https://cdn.signalloomai.com/...",
    "srt": "https://cdn.signalloomai.com/...",
    "vtt": "https://cdn.signalloomai.com/..."
  }
}

Cost Estimation

POST /v1/estimate/free

Get a free cost estimate for any prompt — no API key required.

curl -X POST https://api.signalloomai.com/v1/estimate/free \
  -H "Content-Type: application/json" \
  -d '{"prompt": "Your prompt here", "models": ["gpt-4o", "claude-haiku-4"]}'

POST /v1/estimate

Full cost estimation with API key (tracked against your plan limits).


Webhooks

Configure a webhook URL to receive job results asynchronously:

{
  "webhook_url": "https://your-server.com/webhook",
  "webhook_events": ["job.completed", "job.failed"]
}

Rate Limits

Plan Requests/minute
Free 30
Pro 300
Enterprise Custom

API Reference on GitHub →