On-chain Program

Prova runs on its own Anchor program with native Ed25519 verification — not on a generic attestation service. Four instructions, four events, and a deliberately minimal account model.

Deployment

Program ID (Devnet): G11dBAzLQaADtHHM2AZNz3ThCDnkY5nhX3Ujddu1CMM1
PDA seed:            "prova_agent" + operator_pubkey
Framework:           Anchor 0.31 · Solana CLI 2.1
License:             Apache 2.0 (open source)

Account model

One PDA per operator. Attestations themselves are not stored as accounts — they are emitted as events anchored in the transaction (see Core Concepts → Storage model).

#[account]
pub struct AgentAccount {
    pub operator: Pubkey,          // accountable wallet
    pub agent_id: [u8; 32],        // agent identity (pubkey bytes)
    pub policy_root: [u8; 32],     // Merkle root of the operator's policy
    pub attestation_count: u64,    // lifetime counter
    pub created_at: i64,
    pub revoked: bool,             // kill switch flag
    pub bump: u8,
}

Instructions

Instruction	Arguments	Effect
`register_agent`	`agent_id: [u8;32]`, `policy_root: [u8;32]`	Initializes the agent PDA. Operator signs and pays rent.
`record_attestations`	`attestations: Vec<AttestationInput>`	Seals 1–100 attestations. Requires an Ed25519 verification instruction in the same transaction (checked via the instructions sysvar). Emits one `AttestationIssued` per entry.
`revoke_agent`	—	Sets `revoked = true`. Irreversible; a revoked agent can no longer attest.
`update_policy_root`	`new_root: [u8;32]`	Rotates the policy Merkle root. Emits `PolicyRootUpdated`.

Ed25519 verification

Signatures are verified by the Solana runtime itself: the client prepends an instruction to the native Ed25519 program, and record_attestations inspects the instructions sysvar to confirm the signature over each action_hash was verified in the same transaction. This is cheaper and safer than in-program signature math.

Events

Event	Emitted on
`AgentRegistered`	`register_agent`
`AttestationIssued`	each entry of `record_attestations`
`AgentRevokedEvent`	`revoke_agent`
`PolicyRootUpdated`	`update_policy_root`

Errors

Error	Cause
`AgentRevoked`	The agent was revoked and tried to attest.
`UnauthorizedOperator`	The signer is not the operator that owns the PDA.
`InvalidSignature`	Missing or mismatched Ed25519 verification for an `action_hash`.
`EmptyBatch`	`record_attestations` called with zero entries.
`BatchLimitExceeded`	More than 100 attestations in one call.
`InvalidPolicyRoot`	Malformed policy root.

The program source lives in packages/program of the public repo (github.com/Eras256/Prova) — audits and PRs welcome.