OpenAI

Connect your OpenAI account to use GPT models in Missive.

Connect your OpenAI account to use GPT models for the assistant, prompts, and AI rules.

Missive requires an OpenAI API key, not a ChatGPT subscription. These are separate services with separate billing. Get your API key at platform.openai.com.

Setup

1

Get your OpenAI API key

Create an OpenAI account if you don't have one.

Go to OpenAI Platform and navigate to Settings > API Keys.

Click Create new secret key and copy it somewhere safe. You won't be able to see it again.

(Optional) Find your Organization ID in Settings > General. You'll need this if your OpenAI account belongs to multiple organizations.

2

Add the integration in Missive

In Missive, go to Settings > Integrations > click Add integration > search for OpenAI and click Add to Missive.

Enter your:

• API key (required)

• Organization ID (optional)

Click Add.

3

Share with your team (optional)

To let your team use AI features or create AI rules, share the integration:

Go to Settings > Integrations > OpenAI and click Share integration at the top.

Shared integrations mean everyone uses the same OpenAI API key. All usage bills to your OpenAI account.

Available models

Assistant models

Model	Best for	Speed	Quality
GPT-5.2	Complex reasoning, detailed analysis	Moderate	Highest
GPT-5 Mini	Most daily tasks, good balance of speed and quality	Fast	Good
GPT-5 Nano	Quick tasks, lowest cost	Fastest	Basic

For drafting customer-facing email replies, GPT-5.2 gives the best results. GPT-5 Mini is great for quick tasks like grammar fixes or summaries.

Rule models

Model	Description
GPT-5 Mini	Fast, cost-effective for most tasks (recommended)
GPT-5 Nano	Fastest, lowest cost option for simple classification

Data privacy

OpenAI does not use API data to train models unless you explicitly opt in. Prompts and responses are retained for up to 30 days for abuse monitoring, then deleted.

To confirm data sharing is off, go to platform.openai.com > Settings > Data controls > Sharing and verify all three options are Disabled:

• Enable sharing of model feedback from the Platform

• Share evaluation and fine-tuning data with OpenAI

• Share inputs and outputs with OpenAI

For full details, see OpenAI's data privacy documentation.

Cost and usage

OpenAI bills based on tokens processed (input and output). A token is roughly 3/4 of a word. Check OpenAI's pricing page for current rates.

To put it in perspective: reading a 10-email thread and drafting a reply typically uses 2,000 to 4,000 tokens. At that rate, even heavy daily use of the assistant stays well under a dollar per day with GPT-5 Mini.

Set a monthly budget limit in OpenAI to prevent unexpected charges.

Managing costs

• Use the best model for manual tasks. When you trigger AI yourself (drafting a reply, asking the assistant a question), the cost per interaction is negligible. Use GPT-5.2 for the best results.

• Use cheaper models for AI rules. Rules run automatically on every matching message, so costs add up. GPT-5 Mini or GPT-5 Nano are better choices for classification and routing.

• Add conditions to AI rules. Limit when rules run (e.g., only unassigned conversations, only specific labels) to avoid processing every email.

• Monitor usage. Check your OpenAI dashboard regularly.