Passport

This gives AI agents a cryptographic identity using Ed25519 keypairs, letting them sign manifests and prove their authenticity. You'd reach for this when you need agents to establish verifiable identity across sessions or systems, or when multiple agents need to cryptographically attest to their actions and outputs. The portable identity model means an agent can carry its credentials between environments rather than relying on session tokens or external auth. Think of it as SSH keys for AI agents, enabling trust chains and audit trails in multi-agent systems where you need to know which agent did what.