Deepslate Opal vs Gemini 3.8 Live Extended Thinking

Gemini 3.8 Live Extended Thinking is more reliable, by 11.4 points. Deepslate Opal handled 9 of 70 real callers well on all three runs, and Gemini 3.8 Live Extended Thinking 17. A caller only counts when every run of the call scored 80 or more.

For a voice agent, Gemini 3.8 Live Extended Thinking, since it handles more real callers well on every run. Gemini 3.8 Live Extended Thinking is ahead on ELO rating, turn taking score, speaking score, task handling score, reliability, calls handled well, calls fully resolved and median latency, and Deepslate Opal on hearing score and calls where the agent went quiet.

Gemini 3.8 Live Extended Thinking, by 10.5 points higher. Deepslate Opal fully resolved 12.4% of calls and Gemini 3.8 Live Extended Thinking 22.9%. A call counts only when every step the caller needed was done.

No. Gemini 3.8 Live Extended Thinking starts replying 0.36s sooner at the median. Deepslate Opal takes 2.46s at the median and 3.16s at p90; Gemini 3.8 Live Extended Thinking takes 2.10s and 2.60s. Both are measured on the call audio, from the caller finishing to the agent starting to reply.

Deepslate Opal, by 1.4 points. The agent went quiet for 10 seconds or more on 16.2% of Deepslate Opal calls and 17.6% of Gemini 3.8 Live Extended Thinking calls.

There is no verified per-minute rate for Gemini 3.8 Live Extended Thinking, so cost cannot be compared yet.

Cekura ran both as the whole agent with the same prompt, tools and phone connection. Both took the same 70 recorded real human callers on live calls, three times each. Each call is graded on 25 skills across Hearing, Turn Taking, Task Handling and Speaking, and passes at a score of 80 out of 100.