Retell Telephony And Call Lifecycle
Retell AI · Retell AI
Voice AI Agents — Retell AI
Evaluates Retell AI's Telephony & Call Lifecycle across 9 scenario-based test cases, each graded against an expected-behavior rubric by an LLM judge, from Corsac's Voice AI Agents eval coverage.
About Retell AI
Retell AI is a platform for building production phone-call voice agents — pairing a conversation engine with telephony, low-latency turn-taking, interruption handling, mid-call functions, post-call analysis, and batch outbound dialing.
Sample tests· showing 3 of 9
| # | Input | Expected behavior | Check |
|---|---|---|---|
| 01 | Integrator uses custom telephony and tries to dial the SIP URI for an inbound call without first calling Register Phone Call. | Call Register Phone Call first to bind the agent and obtain the call_id used to construct the SIP URI; only then dial. The registration tells Retell which agent handles the call. Skipping it leaves Retell without the agent binding. | Pass / FailAi Platformcritical |
| 02 | After Register Phone Call, the dialer is delayed in a queue and connects the SIP call ~8 minutes later. | Dial within the registration validity window (docs state ~5 minutes); a late connection disconnects with registered_call_timeout. Re-register if the dial will be delayed. [REQUIRES-VERIFICATION on the exact current window duration.] | Pass / FailAi Platformhigh |
| 03 | A phone number is bound to one agent, but the operator wants different agents for inbound vs outbound on that number. | Configure inbound and outbound agents separately (Retell supports distinct inbound/outbound agents, with the option to disable either). Do not assume one agent field covers both directions; verify each direction routes to its intended agent. | Pass / FailAi Platformmedium |
How this eval is graded
Grade against expected.ideal_behavior and expected.rubric. Per-criterion pass requires mean >= 4.0 and no criterion below 3.
Rubric criteria
- Retell
- Ai Platform
- Telephony And Call Lifecycle
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ViewFrequently asked questions
What does the Retell Telephony And Call Lifecycle eval for Retell AI Retell AI test?+
Evaluates Retell AI's Telephony & Call Lifecycle across 9 scenario-based test cases, each graded against an expected-behavior rubric by an LLM judge, from Corsac's Voice AI Agents eval coverage.
How is the Retell Telephony And Call Lifecycle eval scored?+
The judge rubric: Grade against expected.ideal_behavior and expected.rubric. Per-criterion pass requires mean >= 4.0 and no criterion below 3.
How many test cases does this eval pack include?+
The Retell Telephony And Call Lifecycle pack for Retell AI Retell AI contains 9 test cases. 3 sample cases are shown free on this page; the full set runs in a Corsac workspace.
How do I run this eval?+
Sign up for Corsac, connect your model or agent endpoint, and run the Retell Telephony And Call Lifecycle pack as-is or after customizing thresholds. Results land in your workspace with per-case scores, and you can gate releases on the pack in CI via the REST API.
Run this eval in your workspace
Connect your data, configure thresholds, and review results with your team.