Telnyx is ahead on repeatable reliability, infrastructure reliability, tool call accuracy, voice tone and clarity and response time, and Vapi on interruption handling. The two tie on task completion.
Last updated Methodology by Luis Ojeda
Pick Telnyx for reliability across repeated runs (8.53 points higher), calls that connect and stay up (17.07 points higher), accurate tool calls (0.69 higher), how the agent sounds (0.13 higher) and fast replies (1.26s faster). Pick Vapi for handling interruptions (0.10 higher). They are level on completing the caller's task.
Bars share one scale across all 8 platforms. The place next to each figure is its rank in the field.
Share of the 82 scenarios that passed on all three runs.
Telnyx, 8.53 points higher
Calls where the expected outcome was fully reached.
Level
Calls with no connection, audio or platform failure.
Telnyx, 17.07 points higher
Mean score for calling the right tool with the right arguments.
Telnyx, 0.69 higher
Mean score for how clear and natural the agent sounds.
Telnyx, 0.13 higher
Mean score for yielding and recovering when the caller cuts in.
Vapi, 0.10 higher
Mean time for the agent to start replying after the caller stops.
Telnyx, 1.26s faster
246 calls per platform: 82 scenarios, 3 runs each.
Telnyx is more reliable, by 8.53 points. Telnyx passed 68.29% of the 82 scenarios on all 3 runs and Vapi passed 59.76%. A scenario only counts when every run of it passed.
Telnyx starts replying sooner, 1.26s faster. Mean response time is 1.82s for Telnyx and 3.08s for Vapi.
Telnyx reached the expected outcome on 97.56% of calls and Vapi on 97.56%. They tie on task completion.
Both ran the same Appointment and Medicare agents through the same 82 caller scenarios, 3 times each, with the same evaluators and mock tools. Only the platform and its speech and model components changed.
