vapi

vapi is a skill for Claude Code, Codex from VapiAI/mcp-server. It costs 43 tokens per session (720 once invoked), scanned A, original, MIT.

Guidance for building AI voice assistants and phone agents with Vapi, including conversational applications, phone bots, IVR systems, and outbound calling campaigns.

In plain words
What is it for?
Use it to build or configure voice assistants, automated phone menus, phone agents, and outbound calling systems with Vapi.
Why use it?
It gives an AI coding agent a defined workflow for checking the Vapi connection, handling credentials, and creating voice-based applications.

Skill for Claude CodeCodex

Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

agentmods
npx agentmods add skills/vapiai/mcp-server/skill
Any agent
npx skills add VapiAI/mcp-server --skill skill
Clone the repo
git clone --depth 1 https://github.com/VapiAI/mcp-server

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for vapi

README.md
[![agentmods](https://agentmods.dev/badge/skills/vapiai/mcp-server/skill.svg)](https://agentmods.dev/skills/vapiai/mcp-server/skill)
Your own site
<a href="https://agentmods.dev/skills/vapiai/mcp-server/skill"><img src="https://agentmods.dev/badge/skills/vapiai/mcp-server/skill.svg" alt="Measured on agentmods" height="20"></a>
Per session 43 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 720 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5 $0.00043 $0.00720
Opus 5 $0.00022 $0.00360
Sonnet 5 $0.00009 $0.00144
Haiku 4.5 $0.00004 $0.00072

Measured 4d ago against content hash 685ce34e9e18, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

vapi scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 4d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

skill/SKILL.md · 79 lines

How it starts

The opening of the file, as written. The whole thing — 79 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Vapi - AI Voice Assistant Builder

Build AI-powered voice assistants, phone agents, and conversational AI applications with Vapi.

Workflow

1. Check for the Vapi MCP Server

Check whether a Vapi MCP server is connected by discovering tools such as list_assistants. MCP hosts may namespace displayed tool names with the configured server name.

If the server is unavailable, tell the user to configure one of these supported connections in their MCP host:

  • Local stdio command: npx -y @vapi-ai/mcp-server, with VAPI_TOKEN set in the server environment
  • Remote Streamable HTTP: https://mcp.vapi.ai/mcp, with an Authorization: Bearer <VAPI_TOKEN> header

Tell the user to reload or restart their MCP host if it requires that after configuration.

2. Confirm Vapi Credentials

If a tool returns an authentication error, tell the user to configure a Vapi API key as VAPI_TOKEN for a local server or as the bearer token for the remote server. Then retry after reloading the connection if required by the host.

3. Build the Voice Assistant

Before creating an assistant, fetch the latest prompt engineering guidelines from the Prompt Guide.

Use these guidelines to craft effective voice assistant prompts based on what the user wants to build.

Available Tools

Assistants

  • list_assistants - List all assistants
  • get_assistant - Get assistant details
  • create_assistant - Create new assistant
  • update_assistant - Update assistant

Calls

  • list_calls - List call history
  • get_call - Get call details
  • create_call - Start outbound call

Phone Numbers

  • list_phone_numbers - List phone numbers
  • get_phone_number - Get phone number details

Tools (Function Calling)

  • list_tools - List custom tools
  • get_tool - Get tool details
  • create_tool - Create tool for API integration
  • update_tool - Update tool

Workflow Examples

User: "I want to build a voice assistant that can schedule appointments"

Read the full file on GitHub · 79 lines

Files

What ships with it

1 file beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 4d ago First seen · 79 lines · 43 tokens per session scan A 685ce34e9e18

Subscribe to this mod's changes

vapi is a skill published in the GitHub repository VapiAI/mcp-server (57 stars, last pushed 20d ago), licensed MIT. It adds 43 tokens to every session and 720 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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