Stop testing
your agent
manually.
vspec simulates real phone calls against any AI phone agent — Vapi, Retell, Bland, custom-built, whatever. Just point it at a phone number.
Manual testing
doesn't scale.
Call. Listen. Repeat.
You change a prompt. You call your agent. You listen for 3 minutes. Something's off. You tweak. You call again.
40 times a week. For every scenario. For every agent — regardless of which platform it runs on. You miss edge cases every time.
Define once. Test forever.
Define your test scenarios once — aggressive callers, pricing questions, edge cases. vspec runs them automatically and tells you exactly what passed, what failed, and why.
Change a prompt, run your specs, ship with confidence.
How it works.
Point at a phone number
Connect any AI phone agent to vspec — Vapi, Retell, Bland, Twilio, or fully custom. If it has a phone number, vspec can test it. Setup in under 2 minutes.
Define scenarios
Create test specs via the Web UI: define who's calling, what they want, how they behave, and what success looks like.
Run & iterate
Trigger runs manually in the UI — or automate via API call in your CI/CD pipeline. vspec evaluates outcomes and surfaces exactly where your agent fails.
Your agent is ready
to be tested.
Free tier. No credit card.
Start testing for free →