Voice AI QA for startups

You're shipping fast, and every prompt change is a production risk. Zelto grades every real call, clusters what broke into Findings, and drafts the fix — so nobody on the team spends their nights listening to recordings.

The QA tax on a small team

Every voice AI startup pays it. It just usually doesn't have a name.

Founders listening to recordings

You sample 20 calls out of 2,000 and hope they're representative. The failure costing you customers is in the 1,980 you didn't hear. Zelto grades all of them.

Every prompt change is a gamble

You fix one behavior and quietly break two others, with no regression signal until a customer complains. Zelto grades every call after every change, so regressions surface as Findings within hours.

Scorecards tell you what, not why

Completion rates and latency stay green while the agent gives wrong answers fluently. Zelto grades the conversation itself — against a rubric it learns from your own traffic.

You can't justify QA headcount yet

Hiring reviewers before product-market fit is capital you don't have. Zelto replaces the repetitive 95% of call review, and clusters what it finds so one engineer can act on it.

Built for how startups actually ship

  1. Connect in under 15 minutes

    Native integrations with Vapi, Retell, Bland, LiveKit, Pipecat, ElevenLabs, and Telnyx — or one REST call for custom stacks. No SDK, no agent changes.

  2. Get Findings, not call lists

    Zelto clusters every call that failed for the same reason into one Finding, ranked by how much traffic it costs you. Ten findings, not ten thousand rows.

  3. Ship the fix the same day

    Every Finding comes with a drafted prompt fix and an optional Linear ticket. Hand it to Claude, Codex, or Cursor and close the loop on real production data.

What startup teams ask us

The questions that come up with every early-stage team. Answered honestly.

One week. One agent. Ten findings

Connect one production agent. Zelto listens, then walks you through ten findings with severity, examples, and fixes.

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