---
name: retellai-install-auth
description: "Retell AI install auth \u2014 AI voice agent and phone call automation.\n\
  Use when working with Retell AI for voice agents, phone calls, or telephony.\nTrigger\
  \ with phrases like \"retell install auth\", \"retellai-install-auth\", \"voice\
  \ agent\".\n"
allowed-tools: Read, Write, Edit, Bash(npm:*), Bash(curl:*), Grep
version: 2.0.0
license: MIT
author: Jeremy Longshore <jeremy@intentsolutions.io>
tags:
- saas
- retellai
- voice
- telephony
- ai-agents
compatibility: Designed for Claude Code, also compatible with Codex and OpenClaw
---
# Retell AI Install Auth

## Overview

Install the Retell AI SDK and configure API key authentication for building voice agents.

## Prerequisites

- Retell AI account at retellai.com
- API key from the Retell AI dashboard
- Node.js 18+ or Python 3.9+

## Instructions

### Step 1: Install SDK

```bash
set -euo pipefail
# Node.js
npm install retell-sdk

# Python
pip install retell-sdk
```

### Step 2: Configure Environment

```bash
# .env
RETELL_API_KEY=key_xxxxxxxxxxxxxxxxxxxxxxxx
```

### Step 3: Initialize Client (Node.js)

```typescript
import Retell from 'retell-sdk';

const retell = new Retell({ apiKey: process.env.RETELL_API_KEY! });

// Verify connection — list agents
const agents = await retell.agent.list();
console.log(`Connected! ${agents.length} agent(s) configured.`);
```

### Step 4: Initialize Client (Python)

```python
from retell import Retell
import os

retell = Retell(api_key=os.environ["RETELL_API_KEY"])
agents = retell.agent.list()
print(f"Connected! {len(agents)} agent(s) configured.")
```

## Output

- `retell-sdk` installed
- API key configured
- Connection verified with agent listing

## Error Handling

| Error | Cause | Solution |
|-------|-------|----------|
| `401 Unauthorized` | Invalid API key | Verify key in Retell Dashboard |
| `ModuleNotFoundError` | SDK not installed | `npm install retell-sdk` |
| Connection timeout | Network issue | Check firewall allows HTTPS |

## Resources

- [Retell AI SDKs](https://docs.retellai.com/get-started/sdk)
- [retell-sdk npm](https://www.npmjs.com/package/retell-sdk)

## Next Steps

Create your first agent: `retellai-hello-world`