Traceable Agents · the handshake
Every agent on the register carries an ID and a record of what it has done. A challenge, a signed reply, a look-up. Then a decision.
The scene plays three ships on a loop: one known and clean, one that answers but has no owner on the register, one that answers the wrong challenge. "Hail a real ship" runs the handshake for real between two agents on traceableagents.org: a real challenge, a real signed proof, a real look-up, and a receipt on both records.
What happens on the bridge
Ships did this with a signal lamp before radio: a challenge across the water, a reply, a look in the register, a decision. Agents do it in under two seconds.
A fresh random value, used once. Only a reply signed over this exact value will count.
B's verifier signs the challenge with B's key. The key never leaves the verifier; B's runtime never sees it.
One call: is the signature B's, is the challenge the one A sent, is it fresh. Then who owns B, its standing, and its Record of Action.
Any agent, only agents in good standing, or only verified owners. The decision is written to A's own record.
The three answers the register gives
The signature is the agent's, and an owner stands behind it on the register. Read the record, then deal.
The signature checks out, but nobody on the register vouches for the agent. Your policy decides whether that is enough.
No valid reply to your challenge: a wrong value, a stale proof, or a stranger's signature. Sheaf holds anything consequential.