Developer Guide / OpenAI Account Setup

OpenAI API Platform Setup

How to create the correct OpenAI account, generate an API key, configure billing, and enable realtime model access for Voice Nexus Service.

This must be an OpenAI API Platform account

Do not assume a regular ChatGPT subscription is enough. You must sign up at https://platform.openai.com. A ChatGPT web subscription does not provide the API project, API key, billing setup, or model access configuration required for gpt-realtime in VNS.

Overview

To use gpt-realtime with Voice Nexus Service, you need four things:

1

API Platform Account

A valid OpenAI API Platform account — not just ChatGPT login access.

2

Project + API Key

A project with an API key created with All permissions and stored safely.

3

Billing

Available credits or a payment method enabled on the account.

4

Realtime Model Access

The project's limits must allow models that include the word realtime.

1

Create the OpenAI API Platform Account

  1. 1. Go to https://platform.openai.com
  2. 2. Click Sign Up
  3. 3. Create the account using an email address and password
  4. 4. Open the verification email from OpenAI
  5. 5. Enter the verification code to continue
Recommendation: Use a company-controlled email address rather than a personal email so the API project can remain under business control.
2

Create the Organization and Project

  1. 1. During setup, OpenAI will prompt for an Organization
  2. 2. Optionally invite team members (can be skipped initially)
  3. 3. Create a Project Name
Example project names: VoiceNexus VNS-Production VNS-Test
Best practice: Use separate projects for development and production so usage, keys, and budgets are easier to manage.
3

Create the API Key

  1. 1. Open the selected project
  2. 2. Navigate to API Keys
  3. 3. Click Create API Key
  4. 4. When prompted for Permissions, select All
  5. 5. Copy the key immediately and store it securely
Permissions must be set to All. Keys created with restricted permissions will not have the access required for the realtime API and calls will fail.
Important: The full key value may only be shown once. Save it at creation time. This key goes into your VNS CallStart response as the openAIToken value.
4

Add Billing / Credits

  1. 1. Open the project's Billing area
  2. 2. Add funds or enable the account's payment method
  3. 3. Note: new accounts often start with a low funding limit (e.g., $20)
New-account behavior: New accounts may begin on a low trust tier. As the account matures and is used, higher funding and usage limits become available. Eventually you can enable auto-recharge, set a monthly cap, and increase the per-recharge amount.
5

Enable Realtime Models in Project Limits

This is one of the most important steps. The API key may exist and billing may be funded, but calls can still fail if the project does not allow realtime models.
Project Name (top of screen) → Manage Projects → Select Project → Limits → Edit Model Usage
  1. 1. Click the Project Name at the top of the screen
  2. 2. Select Manage Projects
  3. 3. Click the correct project in the list
  4. 4. In the left menu, click Limits
  5. 5. Under Model Usage, click Edit
  6. 6. Enable all models whose names include the word realtime
  7. 7. Click Save
What to allow: Enable any models such as gpt-realtime gpt-realtime-mini and any newer realtime model variants that appear in the project.
6

Set the Project Budget

Project → Limits → Edit Budget
  1. 1. Stay on the Limits screen
  2. 2. Click Edit Budget
  3. 3. Enter a monthly budget appropriate for expected usage
  4. 4. Click Save
Practical guidance: Start with a budget you're comfortable with, then raise it as call volume grows.
7

Use the API Key in VNS

Once the API Platform account is working, place the API key into your VNS CallStart response as the openAIToken value:

{
  "VoiceElements_Instructions": {
    "openAIUrl": "wss://api.openai.com/v1/realtime?model=gpt-realtime",
    "openAIToken": "sk-YOUR_OPENAI_API_KEY",
    ...
  }
}
Before testing, confirm all of the following:
  • The key was created from the correct project
  • The project has available funds or billing enabled
  • Realtime models are enabled in Limits
  • The exact key value was copied correctly into your VNS configuration
8

Troubleshooting

If the API key does not work, review the error returned in your VNS logs, especially information captured at or near CallEnd.

Error Type Likely Cause Suggested Fix
401 Unauthorized Invalid, incomplete, or revoked API key Regenerate the key and update your VNS configuration
403 Forbidden Model access not enabled for the project Go to Limits and enable all realtime models
429 / Rate Limit Insufficient funded balance or low usage tier Add funds and continue using the account until higher limits become available
Billing Error No credits or payment setup problem Verify billing, available balance, and project budget settings
Common mistake: The user signs into ChatGPT successfully and assumes the API is ready. It is not. They still need the API Platform project, API key, billing, and realtime model permissions separately.

Quick Checklist

Before your first test call, confirm every item below.

  • Customer created an OpenAI API Platform account at platform.openai.com
  • Did not rely only on a ChatGPT subscription
  • Organization and project were created
  • API key was generated with Permissions: All and stored safely
  • Billing or credits were added
  • Realtime models were enabled in Limits
  • Monthly budget was configured
  • API key was inserted into the VNS CallStart response as openAIToken
  • Test call was placed successfully