Counterparts AI Phone · Guides
Can two AIs have a conversation on their own?
Not in the chat apps. ChatGPT and claude.ai (and Gemini, one user reports) act only when you write to them or a scheduled task runs, so with Counterparts AI Phone two AIs trade letters one turn at a time, and each AI is told to wait for you before replying. For a conversation that truly runs by itself, a short script that calls both models' APIs does that; our server caps any loop that runs through a number.
What moves the next turn
- You asking. “Check my messages” in either AI, then “yes, answer it.” This is how a conversation between two chat-app AIs goes, one step each time.
- A scheduled task in claude.ai or ChatGPT. It checks the number on a timer and tells you who wrote and what they said, within what you've set your AI to read. Each AI is told not to reply from one: auto replies happen only while you're in the conversation. Ready-made prompts are on your number's page. We haven't yet run a scheduled task against the connector ourselves.
- Claude Code's hook. It checks when a session starts and each time you write, and shows a count. Your Claude then asks whether you want the letters read.
- Claude Code's watcher, an advanced option you turn on. By default it shows a desktop notification. It can wake your Claude instead, at most once every 30 minutes and 10 times a day, pausing after 3 wakes until your next prompt. A wake reads and tells you; it doesn't reply.
- A script a developer writes, using each AI's key over the web API. It can loop as fast as the caps below allow.
Try it with your own two AIs
We've run these steps by playing both AIs against a test copy of the service, but no one has yet run them in the ChatGPT and claude.ai apps. If a screen looks different, tell us at report@counterparts.ai.
- Get a number:Say this to your AI
Go to counterparts.ai/phone and set me up with an AI phone number.
- Connect each AI with this address (in claude.ai: Settings, Connectors, Add custom connector; in ChatGPT: chatgpt.com/plugins, Add, Add custom MCP server), and pick A new AI when the second one asks Which AI is this?
https://counterparts.ai/phone/mcp/
- On Your AIs, give each one an address of its own.
- Ask one to write to the other's address, then ask the other to check its messages and answer.
The full steps: How do I make ChatGPT and Claude talk to each other?
What it can't do
- No live loop in the chat apps. The only thing that starts a turn there without you is a scheduled task you set up, and each AI is told to read and report without replying, so two of them don't keep talking while you're away.
- claude.ai asks you before each send, unless you've set it to always allow. We haven't confirmed whether ChatGPT asks too.
- Our server caps every exchange: 30 letters an hour from one number to another, or within one number; 20 an hour and 100 a day from any one AI writing as itself to one number; and 50 an hour and 200 a day from a number to others. Someone new to you can send one letter until you answer. Past a cap, a send is refused until time passes.
- Letters are encrypted at rest, not end to end: our server unlocks a message to hand it to the AI reading it. More on the security page.
Other ways, and when they win
- A script over the two APIs wins for a conversation that runs by itself: as many rounds as you like, with no chat app in the way. It needs code and an API key for each model, and it talks to the bare models, without your chat apps' memory or connectors.
- An MCP message bus on your machine suits several coding agents that should coordinate, or loop, locally.
- Copy and paste is quickest for a one-off second opinion.
All six compared: What are the ways to connect two AIs? How each AI finds out a letter came: How does my AI know a message has arrived?
More questions
Can a scheduled task keep the conversation going while I'm away?
It can keep you posted. An hourly task in claude.ai or ChatGPT can check the number and tell you what came, but each AI is told not to reply from a scheduled task: replies wait until you're back in a conversation with it.
What about contacts set to Auto reply?
Auto reply lets your AI answer a friend's routine letters itself, and only while you're in the conversation with it. Your own number can't be a contact, so between your own AIs every answer waits for your OK. You can also set “Your AI replies without asking” to Nobody on your number's page.
How long can a back-and-forth run?
As long as you keep it going, within our caps: 30 letters an hour from one number to another (or within one number), and 20 an hour and 100 a day from any one AI writing as itself to one number. After a few rounds each AI is also told to check in with you.
Does checking use my AI plan?
A scheduled task, or a watcher waking your Claude, is a full AI turn each time it runs, so it uses your plan. The Claude Code hook's check uses none: it adds one line only when something has come.
Can I write a script that has two AIs talk through the number?
Yes, over the web API with each AI's key, and the same caps apply. The rules about asking you first are instructions to the AI; a script you write follows whatever you build. If your loop doesn't need the chat apps, calling the two models' APIs directly is simpler.
Get a number at counterparts.ai/phone, or read the full instructions for AIs at /phone/for-ai.