Introduction
# Vapi Calls - Agent Instructions
Use this skill to perform any task that requires voice interaction over the phone.
## Configuration & Network Requirements
⚠️ **IMPORTANT:** This skill requires your machine to be reachable from the internet to receive real-time call updates.
### 1. Environment Variables Configure these in your OpenClaw `config.json` (or Gateway env):
- `VAPI_API_KEY`: Your Vapi Private API Key. - `VAPI_ASSISTANT_ID`: The ID of the Vapi Assistant to use as a base. - `VAPI_PHONE_NUMBER_ID`: The ID of the Vapi Phone Number. - `WEBHOOK_BASE_URL`: **Crucial.** The public HTTPS URL where this agent is reachable (e.g., `https://my-claw.com` or `https://xyz.ngrok-free.app`). **Do not include a trailing slash.** - `WEBHOOK_PORT` (Optional): The local port to listen on (Default: `4430`). - `VAPI_LLM_PROVIDER`: (Optional) Provider for Custom Mode (Default: `openai`). - `VAPI_LLM_MODEL`: (Optional) Model for Custom Mode (Default: `gpt-4o-mini`).
### 2. Connectivity Setup You must expose the `WEBHOOK_PORT` (default 4430) to the internet.
**Option A: Cloudflare Tunnel (Recommended)** `cloudflared tunnel --url http://localhost:4430`
**Option B: Ngrok** `ngrok http 4430`
Set `WEBHOOK_BASE_URL` to the generated URL (e.g., `https://random-name.trycloudflare.com`).
## Usage
### Custom Mission (Dynamic) Provide a specific `system_prompt`. The system will automatically use **GPT-4o Mini** and enable the **endCall** tool. The AI will be able to hang up autonomously.
### Native Agent (Static) Pass `"DEFAULT"` for `first_message`, `system_prompt`, and `end_message`. The system will use the exact configuration (Model, Voice, Prompt) defined in the Vapi Dashboard.
## Troubleshooting
- **Call hangs / No report:** Check if `WEBHOOK_BASE_URL` is reachable from the internet. The Python script spins up a temporary server on `WEBHOOK_PORT` only during the call. - **API 400 Error:** Check your `VAPI_PHONE_NUMBER_ID` and `VAPI_ASSISTANT_ID`.