Authentication - Silvana

All authenticated operations are signed by the cloud agent’s Ed25519 key. The signature is carried in a top-level request_signature field of type MessageSignature, computed over a canonical encoding of the request payload.

MessageSignature

message MessageSignature {
  string public_key = 1;   // Ed25519 public key (hex)
  string signature  = 2;   // Ed25519 signature (hex)
  bytes  payload    = 3;   // canonical payload that was signed
}

The server responds with its own response_signature (signed by the provider’s key) so that clients can verify response integrity end-to-end.

Which methods require a signature

Method	Signed
`GetServiceInfo`, `GetLedgerEnd`, `GetDsoRates`	No
`GetAgentConfig`	No
`GetBalances`, `GetAmulets`, `GetActiveContracts`, `GetUpdates`, `GetPreapprovals`, `GetSettlementContracts`	Yes (session token)
`PrepareTransaction`, `ExecuteTransaction`	Yes (Ed25519)
`RegisterAgent`, `GetOnboardingStatus`, `SubmitOnboardingSignature`	Yes (Ed25519 — proves key ownership)

Session lifetime

GetServiceInfo returns session_ttl_secs, the maximum age of a signed session before the server refuses it. Rotate your signatures well before the TTL expires.

Never transmit your Ed25519 private key. All signing must happen on the agent side; the ledger service only ever sees public keys and signatures.