Add another computer

A machine you already trust lets the new one in, over SSH, with no account and no service in the middle.

You will be able to let a second machine open your mineral, admitted by one that already can.

Your identity on your mineral is an SSH key, one per computer. So a new laptop does not sign in to anything: a computer that already opens the mineral vouches for it, directly to your own box. There is no account, no email, and no Crads-AI service anywhere in the chain.

You need both machines in front of you (or a way to copy two short strings between them). The whole thing takes about two minutes.

On the new computer#

  1. Open the Crads AI app. On the door, choose I already have one.
  2. Type the mineral's name, exactly as it was set up ("the name it was set up with" is the prompt, and a wrong guess is refused later rather than installed under a mismatched name).
  3. Press Show this computer's key. A single line appears, starting ssh-ed25519. Copy it.

On the computer that already opens the mineral#

  1. Open the app. Find the mineral in the list and choose Add a device.
  2. Paste the new computer's key and confirm.
  3. The app appends the key to the box's own door over SSH, and answers with a connection bundle: one line starting crads1:. Copy that back to the new computer.

The paste is strict on purpose: exactly one key line is accepted, and anything else (a second line, a stray character) is refused rather than smuggled in. Appending the same key twice changes nothing.

Back on the new computer#

Paste the bundle and confirm. The app repairs its connection details from the bundle, pins the box's host key before first contact when the bundle carries one, then proves the whole chain with a real connection and says honestly whether the mineral answered. When it does, this computer is in: same mineral, same brain, same assistant.

What just happened, in one paragraph#

The old machine appended the new machine's public key to authorized_keys on your box, which is the one list the door reads (machines that can open your mineral is that list's page). The bundle carried the box's address and host key back so the new machine knows both where to connect and that it is talking to the right server. At no point did anything leave the three machines you own.

If it does not connect#

  • "That name does not match": the mineral's name on the new computer must be the name the bundle was minted for. Re-run the offer with the right name.
  • The probe says the mineral did not answer: the box may be restarting or the address unreachable from this network. The bundle is still good; try again in a minute.
  • No second computer any more (lost, wiped, stolen): a machine can also be let in over plain SSH by anyone who still holds a working key, and if no working key exists anywhere, the box is sealed by design; that is what the backup exists for. If a machine was stolen, remove its key from the roster first.