Most people who run a voice agent do it from a dashboard. You log in, find the worker, read through a transcript, fix a sentence in the script, enter the numbers to be called tomorrow morning. Nothing wrong with that. It is just one more place you have to remember to go.
Threll has an MCP server. It moves those same operations into the chat you are already in.
Two levels of AI, and they keep getting mixed up
Worth separating clearly, because they live in the same sentence whenever people talk about “AI that calls”.
The voice agent is the one that calls. It speaks Norwegian, Swedish or Danish, follows its script, and does the job in real time while a human is on the line.
The orchestrator is the AI you sit in yourself – Claude, ChatGPT, Gemini or Microsoft Copilot. It calls no one. It does what you used to do with the mouse: lists workers, reads call history, pulls last week's numbers, suggests a change to the script, prepares a round of calls.
“Set it up so Harald calls these five tomorrow at nine, reminding them the contract is expiring” becomes a prepared, confirmed and scheduled round. You wrote one sentence.
The gain is not that it is faster than clicking. The gain is that the orchestration happens in the same place as the rest of your work – in the same conversation where you also have your CRM, your calendar and your inbox.
What MCP is
Think of it as a standard socket.
Before MCP, every vendor had to build its own connection to every AI service: Threll to Claude, Threll to ChatGPT, Threll to Gemini, Threll to Copilot – and the same again for every other vendor, over and over. With MCP we build one connection, and any AI tool that supports the standard can use it. Which is why this is one article rather than one per AI tool.
For you, putting it to use is simpler than it sounds. You paste one address – https://mcp.threll.io – into the AI service you use. You are then sent to Threll, log in the way you always do, pick the account it applies to, and approve what the AI is allowed to do. No API keys, nothing to copy back and forth, nothing you have to renew manually later.
What you approve is bounded. A connection can be set up to read only – call history, transcripts, numbers – or to place calls and make changes as well. The AI never gets more than you said yes to at login, and it cannot help itself to more along the way: if it needs more, you approve again. It also never gets more than you have access to yourself.
What it can do sits close to what you find in the interface:
| What you want to do | What the AI gets to see and do |
|---|---|
| See who exists and how they are set up | Workers, language, phone numbers, active or not |
| Call out, schedule, cancel | Single calls and rounds of up to a hundred, always with confirmation |
| Dig into what has happened | Call history, transcripts, events, numbers |
| Change what the agent says | The call script documents: fetch, propose a new version, take out of use |
| Keep track of who gets called | People and leads, one at a time or as an import |
And one thing you will not find in the interface in the same form: a confirmation before anything rings.
The confirmation is not a formality
Placing a call is the one action the AI can take here that reaches the world outside. So it is blocked by default, and outbound calls happen in two steps.
The first step calls no one. It produces a proposal: which worker, from which number, to whom, when, and with what instructions. The AI shows you the proposal. The call goes out only when you say yes – and an approval can be used only once, so the same round cannot go out twice by accident.
That applies to larger rounds too. If eighty customers are to be called, the whole list is checked up front and approved as one: either all of them go into the queue, or none do. Change your mind before you have said yes, and the proposal is discarded without anything being sent.
Read the proposal. That is the whole reason it is there.
How to connect
Claude
- Open Customize → Connectors.
- Click + and choose Add custom connector.
- Paste
https://mcp.threll.ioand add it. - Complete the login on Threll's page, pick the account, approve the access.
- Turn the connector on in the conversation where you want it.
On Team and Enterprise, members cannot add their own connectors. An owner adds it under Organization settings → Connectors first, and then each member connects with their own login. That split is deliberate: the AI never gets more access than the person using it.
ChatGPT
Custom connectors sit behind developer mode, and that is the part people do not find.
- Go to Settings → Apps & Connectors → Advanced settings and turn on Developer mode.
- Go back to Connectors and choose Create.
- Fill in a name,
https://mcp.threll.io, and pick OAuth as the login method. - Acknowledge the notice about custom connectors.
- Complete the login to Threll.
- In the conversation: Tools → Use apps, and switch it on.
This requires a paid plan. On Business, Enterprise and Edu, an administrator has to allow developer mode for the workspace first – if the toggle is missing, that is usually policy rather than a fault. ChatGPT is stricter than the others about how a server identifies itself, but Threll's server meets the requirements, so there is nothing for you to create manually.





