Testzilla

Testing infrastructure, not just a testing tool

You did not build your voice agent from scratch. You built it on Retell, Vapi, ElevenLabs, or one of many other platforms. Testzilla works the same way: it is the testing layer you plug in alongside the platforms you already use, not another platform you have to migrate to.

Testzilla is vendor-neutral but vendor-interactive. It does not care which provider you chose, and it drives your real agents on those providers: it places real phone calls, opens your live chat widget in a real browser, and runs real WebRTC voice sessions against the agent you actually shipped. The results reflect what your users get, not a simulation.

Bring the agents you already have Point Testzilla at an existing Retell, Vapi, ElevenLabs, or other-platform agent. No rebuild, no migration, no SDK lock-in.

Use the same tests on every platform Write your scenarios once and run the identical suite across multiple systems and providers — chat, phone, widget, and voice — for an apples-to-apples comparison.

Catch regressions before production Run the same suite on every deploy and track quality over time, so a prompt change that breaks booking shows up in a test, not a support ticket.

Test the real surface Real phone calls, real chat widgets in a real browser, real WebRTC voice. Testzilla exercises the path your users take.

Synthetic data by design The agent under test is AI and the tester is AI — no real customer PII is needed — so you avoid platform vendor-lock on your testing, too.

Start here

Quickstart (no code) Sign up and get your first test result without writing a line of code, using the setup wizard and the Tessie assistant.

Test a Phone Number The fastest path: test an agent that lives on a phone number.

Test your agent by channel

Pick the surface your agent runs on. Each guide is a single how-to, end to end.

Test a Phone Number Live inbound phone calls — Testzilla dials your agent. Outbound coming soon.

Test Web Chat A real chat widget on a live website.

Test Web Voice A browser WebRTC voice session.

Test an LLM The agent's text LLM directly, fast and cheap.

Use it with your provider

Testing Retell Phone, LLM Chat, Web Chat, and Web Voice for Retell agents.

Testing Vapi Phone and Web Voice for Vapi assistants.

Testing ElevenLabs Web Voice for ElevenLabs Conversational AI agents.

Integrate it into your workflow

Once you are testing in the app, wire Testzilla into your own tooling.

Integrate via MCP Drive Testzilla from an AI agent like Claude Code or Cursor.

Integrate via API Automate projects, channels, tests, and runs over REST in CI.