Codersarts Blog.

Sales reps lose deals in the moments they can't see themselves — talking over the prospect, missing a buying signal, going silent when objections hit. A coach whispering in their ear would fix most of that. Most companies can't afford one per rep. An AI agent listening to the live call can be that coach. Here's how to build one using the OpenAI Realtime API for low-latency audio understanding and LangGraph to orchestrate the coaching logic. Why This Stack OpenAI Realtime API