Voice AI Yeastar P550 Integration

I want to wire Vapi’s Voice AI directly into my Yeastar P550 PBX so every outbound call to potential customers is handled automatically. The goal is true hands-free cold calling: the system should pick numbers from my lead list, place the call through the P550, open with an AI-generated script, hold a natural conversation, and either book the meeting or pass the call to a live agent when certain triggers are met. You’ll need to bridge Vapi’s API with the P550 via SIP or an equivalent method, build the call flow inside Yeastar (dial plans, queues, or IVR branches as required), and make sure the audio streams cleanly in both directions with minimal latency. I already have both Vapi and the PBX accounts active; what I don’t have is the middleware that lets the two talk to each other. Deliverables • Working integration between Vapi Voice AI and Yeastar P550, fully tested on live calls • A simple dashboard or config file where I can upload a CSV of potential-customer numbers and tweak the opening prompt • Clear setup documentation so I can redeploy or clone the environment later • Brief hand-off session to walk me through the call flow and troubleshooting steps Acceptance criteria: calls must connect through the PBX, the AI must handle at least 90 % of common objections without human intervention, and hand-offs to a real agent must complete in under five seconds. If you’ve previously connected third-party AI voice tools to on-prem or cloud PBXs, this should feel familiar. Let me know which similar projects you’ve done and the typical tech stack you prefer.