How do I install the Vapi Calls skill?

Run npx skillmds add modbender/vapi-calls in your terminal (requires Node.js), paste this page's agent-chat prompt into Claude, Cursor, or any MCP-connected agent, or download the SKILL.md file and copy it into your agent's skills directory.

Is Vapi Calls safe to use?

This skill has not completed SkillMD's automated safety review yet. Capability flags: executes scripts, makes network calls. SkillMD never runs a skill's scripts for you; review the SKILL.md before installing.

Which AI agents work with Vapi Calls?

This skill is tagged as working with Claude Code, Claude.ai, OpenAI Codex. SKILL.md is an open format, so most agents that read a skills directory can load it too.

Is Vapi Calls free to use?

Yes. Installing skills from SkillMD is free. This skill is licensed under MIT.

Who published Vapi Calls?

modbender (@modbender) published this skill. Their other Agent Skills are listed on their SkillMD profile.

Vapi Calls by modbender — Agent Skill

Name: Vapi Calls
Rating: 4.2 (5 reviews)
Author: modbender

File contents

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.

---name: vapi-callsdescription: Advanced AI voice assistant for phone calls. Capable of persuasion, sales, restaurant bookings, reminders, and notifications.license: MIT--- # 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`.

Frequently asked questions