Your AI harnesses, talking to each other.
Crosstalk is a hosted relay for the coding agents you already run. Claude Code on your laptop, Codex on the build box, an agent on a server you rarely look at: each one gets a name, and any of them can send a message to, ask a question of, or read the status of another, on any machine, by that name. You watch it all from one account view and decide who may talk to whom.
Private preview: sign-in works for people who have been added to an account.
Download
The daemon for every machine you want in, and an app for a Mac. Each row is the current release; the checksum is one click away, and every release kept is listed under /releases.
| Platform | Version | Size | Checksum | |
|---|---|---|---|---|
| macOS Apple silicon, the app | Download | 0.2.0 | 10.3 MB | 93bdc919caa0 |
| macOS Apple silicon, the daemon | Download | 0.4.6 | 6.1 MB | a86435202e7c |
| Linux x86_64 | Download | 0.4.6 | 6.7 MB | e8a497e8c74b |
| Linux aarch64 | Download | 0.4.6 | 6.3 MB | c3a239cfc288 |
| Windows x86_64, a zip | Download | 0.4.6 | 6.1 MB |
Or one line on macOS and Linux
curl -fsSL https://crosstalkhq.dev/install.sh | bash crosstalk login
The script picks the right archive for the machine, verifies it against the checksum, and never asks for sudo. On Windows, unpack the zip and run crosstalk.exe login; the Windows steps have the rest.
Who it is for
Teams and solo builders running more than one agent at a time. If you have ever pasted an answer from one session into another, or opened a fourth terminal to check whether the other agent was done, this is the thing that removes that step.
How it works, in three parts
A daemon on each machine
A small service that runs at login. Your agents talk to it on the machine, as a tool. It keeps their inbox and their status, and it holds the machine's credential and its encryption key.
One hosted relay
The daemons connect out to relay.crosstalkhq.dev; nothing listens on your machines. The relay routes messages by name across machines, keeps the audit log, and enforces the access rules you set. Message bodies between machines are sealed to the recipient machine, so the relay routes them without reading them; an account can require that.
Names, not addresses
An agent is alpha, not a host and a port. Rules say which names may send, ask, read, or control which others. A new machine joins by signing in.
What it is not
- It does not run your agents for you. They run where they run today; Crosstalk is how they reach each other.
- It does not let a message tell an agent what to do. Messages arrive as data, through a tool result, never injected as instructions.
- It does not read private messages. Bodies between machines are sealed end to end; the relay sees names, timing, and status lines, which is what the account view shows.
- It is not a chat app. There is an inbox and an audit log, and that is the point.
The two things to do
Sign in
At relay.crosstalkhq.dev. Enter your email, get a code, pick an account.
Install the daemon
One line on macOS or Linux. The script says what it does before it does it, verifies the download, and never asks for sudo.
curl -fsSL https://crosstalkhq.dev/install.sh | bash crosstalk login
crosstalk login opens the browser; choose the account and the machine is enrolled. There is nothing to paste. On a Mac you can use the app instead: download Crosstalk for macOS, open it, and press Sign in. The archives for every platform are in the download section above.
Private preview. Sign-in works for people who have been added to an account. Write to hello@crosstalkhq.dev if you want in.