Who should use Zelto?

Zelto is a B2B product built for voice AI developers.

Yes — there is a free tier, with paid plans for advanced use.

Is Zelto still active?

Unverified. Zelto has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.

What are alternatives to Zelto?

Similar projects tracked by PulseGate include constraintloop, trajectory-judge, and DeFake.

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Zelto

Name: Zelto
Author: Zelto

zelto.aiLLM eval & observability

Zelto provides quality assurance for voice AI agents by processing production calls in real time. It automatically detects issues, groups similar failures into Findings ranked by impact, and suggests specific fixes that map to key metrics. Designed for teams building agents with platforms like Vapi, Retell, and LiveKit, it turns thousands of calls into actionable insights that improve agent performance over time.

FreemiumWebCloud-managed

Visit zelto.ai

Overview

5 features

Zelto sits in PulseGate's LLM eval & observability category. It focuses on understanding why voice AI agents fail in production calls and identifying the highest-impact fixes. Zelto is a B2B product aimed at voice AI developers. There is a free tier. Zelto is available on the web.

It is developed by Zelto, and it first shipped in 2024. Among its 5 catalogued features are Call Analysis, Failure Clustering, and Real-time Streaming. It exposes integrations via a public API.

Summary written by a language model from the project’s public pages.

Call Analysis
Failure Clustering
Real-time Streaming
Automated Fixes
Metric Mapping

Built with & integrations

Framework

Next.js

Hosting

Vercel

Connectors

API

Runs on

BrowserCloud-managed

Detected from

Next.js: x-nextjs-prerender header · /_next/static/ in the HTML · __next_f in the HTML
Vercel: x-vercel-id header · x-vercel-cache header

Trust & compliance

Verified signals

HTTPS

Indexing history

What PulseGate has recorded for this listing

Indexed25 Jul · 19:14 UTC
Zelto verified against its public source
Source: PulseGate · Open

Frequently asked questions about Zelto

What does Zelto do?: Zelto focuses on understanding why voice AI agents fail in production calls and identifying the highest-impact fixes. It is catalogued under LLM eval & observability on PulseGate.
Who should use Zelto?: Zelto is a B2B product built for voice AI developers.
Is Zelto free?: Yes — there is a free tier, with paid plans for advanced use.
What platforms does Zelto run on?: Zelto runs on the web.
Is Zelto still active?: Unverified. Zelto has not been re-checked since it entered the index, so there is no finding either way — and only a positive finding would say otherwise.
What are alternatives to Zelto?: Similar projects tracked by PulseGate include constraintloop, trajectory-judge, and DeFake.constraintloop trajectory-judge DeFake
Who develops Zelto?: Zelto is developed by Zelto.
How long has Zelto been around?: Zelto first shipped in 2024.

At a glance

Pricing: Freemium · pricing page detected
Platforms: Web
Languages: English
Built for: voice AI developers
Model: B2B
Solves: Understanding why voice AI agents fail in production calls and identifying the highest-impact fixes.

Live coverage

Identity confidence: High · 87.8
Indexed: 25 Jul 2026
Lifecycle: Alive
Last seen: 25 Jul 2026

Identity audit (13)

Slug: zelto-zelto-ai
Lifecycle state recorded: 25 Jul 2026
Verification state: Indexed for public listing
Listing state: Listed: yes
Index status: Included in index
Latest evidence snapshot: 25 Jul 2026
Timeline basis: Indexed-at chronology. This listing's first-seen date was written by the catalog backfill, not observed here, so it is not treated as a sighting.
Name from: Derived from the project's own page and URL.
Category from: Assigned by a language model.
Summary from: Written by a language model from public pages.
Languages from: Detected by a language model, checked against the page's own declaration.
Last updated: 5 Aug 2026
Canonical URL: https://zelto.ai/

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