GPT Actions that make phone calls via the OpenAPI 3.1 spec.
Import the FoxEra Calls OpenAPI spec into a custom GPT so it can add leads, preview campaigns, and run AI cold calls after your approval. Bearer key, no code.
What a GPT Action is and why it needs FoxEra
A GPT Action is a way to give a custom GPT the ability to call an external API. You provide an OpenAPI spec, configure authentication, and the GPT can then use those endpoints as tools during a conversation.
On its own, a custom GPT has no phone line and no voice engine. It cannot dial a number or hold a conversation with a prospect. When you connect it to FoxEra Calls via a GPT Action, the GPT gains access to the full calling toolset: adding leads, choosing an AI agent, previewing campaigns, and running them after your approval. FoxEra’s AI calling agents (Cass, Alex or Andrea) handle the actual phone conversation.
How to set up the GPT Action
- Create the API key: sign in to FoxEra Calls, go to your account settings, and generate a bearer key (
fxk_...). - Create or edit a custom GPT: in ChatGPT, open the GPT editor and go to the Actions section.
- Import the spec: paste https://app.foxera.co.uk/api/public/openapi.json into the schema URL field. ChatGPT will load the available operations automatically.
- Set authentication: choose API Key as the auth type, select Bearer, and paste your
fxk_...key. - Save and test: open the GPT and ask it to check your FoxEra account balance. If it returns a number, the connection is working.
The whole setup takes a few minutes. Full details are on the developer guide.
What the custom GPT can do once connected
With the Action active, you can ask your custom GPT to handle most calling tasks in plain English:
- Check your account balance and available credit
- Add leads individually or upload an entire folder of contacts
- Choose which AI calling agent (Cass, Alex or Andrea) will make the calls
- Preview the campaign: headcount, calling window and estimated cost
- Create, schedule and approve a campaign after you have reviewed the preview
- Cancel or stop a live campaign immediately
- Read call outcomes, transcripts and recordings after the calls finish
- Set calling hours so calls go out only during the window you choose
- Edit or approve the calling script your AI agent follows
- Pull a report covering outcomes and cost, or get a link to top up credit
You can also use this GPT from the ChatGPT mobile app, so your calling campaigns are manageable from anywhere.
Why the approval step still applies inside a GPT
FoxEra requires the exact confirmed headcount and a separate approval before anyone is phoned. This rule applies regardless of how the campaign was created: from the dashboard, an AI assistant, or a custom GPT.
In practice, when your GPT creates a campaign it will show you the preview (how many people, the estimated cost, the calling window) and ask you to confirm. Nobody is called until you say yes. Every action is logged inside your FoxEra workspace, so you can see exactly what the GPT did and when.
You can revoke the API key at any time. The key acts only inside your own workspace and cannot reach any other account. For more on the safety model, see how FoxEra Calls works.
Bearer key vs MCP connector
GPT Actions use bearer-key authentication against the REST API. If you prefer the MCP route instead, you can use the ChatGPT custom connector approach: add https://app.foxera.co.uk/mcp as a connector and authenticate with OAuth 2.1. Both routes give you the same calling tools; the difference is how you authenticate.
The bearer key is simpler if you only need one custom GPT to manage your calls. The MCP connector is better if you want multiple assistants (ChatGPT, Claude, Cursor) all connected to the same workspace. See the developer guide for a side-by-side comparison.
What it costs
Creating a GPT Action and connecting it to FoxEra Calls is free. You pay only for the calls themselves: from 12p per connected minute, with no subscription and no seat fee. Every new FoxEra account gets £7 of free calling credit, enough for a short test campaign.
Use the cost calculator to estimate what your first run will cost. The full pricing breakdown is on the pricing page. If you want to understand how pay-as-you-go calling compares to monthly subscriptions elsewhere, that page covers it.
Frequently asked questions
Can a custom GPT actually make phone calls?
Not on its own. A custom GPT has no phone line. When connected to FoxEra Calls via a GPT Action, it tells FoxEra which leads to call and when. FoxEra’s AI agents (Cass, Alex or Andrea) make the actual phone calls and record the conversations.
Do I need a developer to build this?
No. You import the OpenAPI spec URL, set authentication to Bearer, paste your API key, and save. The GPT editor handles the rest. No code is required.
Will the GPT call people without asking me first?
No. FoxEra requires you to confirm the exact number of people and approve the campaign separately before anyone is phoned. The GPT shows you the preview and waits for your yes.
How much does a first test campaign cost?
New accounts get £7 of free calling credit. Calls cost from 12p per connected minute with no subscription, so a short test of 20 to 30 leads typically costs a few pounds.