OpenAI

Pro plan. OpenAI works through a connection and HTTP steps, which are part of Pro and Agency (and the free trial). Anything you already have keeps working on every plan. See Plans and billing.

A Webhook / HTTP step sends the contact’s headline, title and company to OpenAI with your prompt and your model. The answer is available to the next message. Kerux also has its own AI (the Ask AI step, reply types, writing help), paid with Kerux’s AI credits. This guide is for teams that want their own OpenAI account, model and prompts.

How it connects: OpenAI’s API with your key as a bearer token. See OpenAI’s Chat Completions reference. The answer below follows OpenAI’s docs; the model id is yours to choose.

Before you start

OpenAI billing: the API is billed per token on your OpenAI account, separately from ChatGPT plans.
An API key: create a project key in the OpenAI platform.
Data: only the fields you put in the prompt go to OpenAI, under your agreement with OpenAI.

1. Connect OpenAI

In Kerux, open Integrations > Connections, click Connect on Custom API (under Developers):

How it signs in: Bearer token, paste the key.
Base URL: https://api.openai.com

Click Save, then Test connection.

2. Ask for the line

Add a Webhook / HTTP step named openai, pick the connection:

{
  "method": "POST",
  "url": "/v1/chat/completions",
  "bodyType": "json",
  "body": {
    "model": "YOUR_MODEL_ID",
    "messages": [
      { "role": "system", "content": "Write one friendly opening line for a LinkedIn message. No greeting, no emojis, under 25 words." },
      { "role": "user", "content": "Title: {{contact.title}}. Headline: {{contact.headline}}. Company: {{contact.company}}." }
    ]
  }
}

OpenAI answers (trimmed):

{ "choices": [{ "message": { "role": "assistant", "content": "Saw Northwind is opening a Berlin office, congrats." } }] }

In the next message: {{steps.openai.response.body.choices.0.message.content}}, followed by your own text.

3. Keep it safe

Test on a few contacts before launching, and read the lines.
If the call fails, the contact stops in Needs attention with OpenAI’s message; nothing odd goes out.

Test with one contact

In the Builder, click Test to open Test on one contact. The journey shows the prompt that was sent and OpenAI’s answer.

Common errors

401 invalid_api_key

The key is wrong or was revoked. Create a new one and edit the connection.

404 model_not_found

The model id is wrong or your project can’t use it. Check the model in OpenAI’s docs and your project’s limits.

429 rate limit or insufficient_quota

Too many calls, or no credit left on the account. Kerux retries rate limits later; add credit for quota errors.

Getting started

Campaigns

Account safety

Inbox

Contacts

Integrations

Integration guides

Developers

Account & billing

Help

Before you start

1. Connect OpenAI

2. Ask for the line

3. Keep it safe

Test with one contact

Common errors

​Before you start

​1. Connect OpenAI

​2. Ask for the line

​3. Keep it safe

​Test with one contact

​Common errors

Before you start

1. Connect OpenAI

2. Ask for the line

3. Keep it safe

Test with one contact

Common errors