Free during beta · 100 calls / month included

See every word your voice agents say.

Production-grade observability for voice AI. Latency breakdown, transcript search, hallucination detection — purpose-built for Vapi, Retell, Bland, and OpenAI Realtime.

No credit card · Connect Vapi in 60 seconds

Built for the leading voice AI platforms

VapiRetellBlandOpenAI RealtimeLiveKit

Built for voice

Generic LLM tools weren't designed for this.

Helicone and Langfuse see prompts and responses. Voice agents have transcripts, audio, function calls, latency budgets, and hangup signals. We see all of it.

Latency breakdown

STT, LLM, and TTS time isolated per call. P50/P95 across every agent.

Hangup analyzer

Cluster calls by why they ended. Find the call that lost you the customer.

Hallucination detection

When the AI claims something it shouldn't know, we flag it. You investigate.

Function call telemetry

Every tool invocation tracked. Success rate, retries, payload shape, time-to-tool.

Custom evals

Define quality rubrics in plain English. Claude evaluates every call against them.

Semantic search

Find calls by meaning, not keywords. 'Customers asking about refunds' just works.

What you see

Every call, decomposed.

Transcripts, sentiment, intent, CSAT estimate, latency P50/P95, function call success — analyzed by Claude in under 2 seconds.

  • Real-time webhook ingestion
  • Speaker diarization with turn-level metadata
  • Cost tracking per agent, per call
  • Customizable alert rules
call_019e320d
duration50s
sentimentneutral
latencystt 368ms · llm 497ms · tts 620ms
[AI]Hi, thanks for calling. How can I help today?
[User]Hey, it's the patient side. I called about my order.
[AI]Happy to help. Can I start with your name?
topics
order inquirycustomer infocallback

Pricing

Cheaper than the alternatives.

We undercut Helicone, Langfuse, and LangSmith — and we're built specifically for voice. Start free, upgrade when you outgrow it.

Free

$0forever

100 calls/mo

  • Unlimited integrations
  • Latency breakdown
  • Email alerts (soon)
  • 30-day retention
Start free
Popular

Starter

$29per month

1,500 calls/mo

  • Unlimited integrations
  • Latency breakdown
  • Email alerts (soon)
  • 30-day retention
Start free

Growth

$99per month

10,000 calls/mo

  • Everything in Growth
  • Multi-org
  • SSO (soon)
  • 1-year retention
  • Priority support
Start free

Scale

$299per month

50,000 calls/mo

  • Everything in Growth
  • Multi-org
  • SSO (soon)
  • 1-year retention
  • Priority support
Start free

Overage above plan: $0.015 per call. Alerts at 80% / 100% / 120% — no surprise bills.

Pricing covers VoiceObs only. You bring your own Vapi or Retell account and pay them directly for calls — VoiceObs analyzes the data, it doesn't replace your provider.

Voice AI, observed.

Start with 100 free calls per month. Upgrade when you need more.

No credit card required