Architecture

System design and data flow of the Aegis Protocol.

High-Level Architecture

┌─────────────────────┐
│   Vault Owner       │ (Human)
│   - Browser Wallet  │
└──────────┬──────────┘
           │ Signs vault management
           ▼
┌─────────────────────┐
│   Aegis Protocol    │ (On-chain)
│   - VaultConfig PDA │
│   - Policy Engine   │
│   - Fee Collection  │
└──────────┬──────────┘
           ▲
           │ Signs transactions
┌──────────┴──────────┐
│   AI Agent          │ (Autonomous)
│   - Server Keypair  │
└─────────────────────┘

PDA Derivation

Vault Config PDA

Seeds: ["vault", authority, nonce]
Purpose: Stores vault configuration

Vault Authority PDA

Seeds: ["vault_authority", vault_pda]
Purpose: Holds actual SOL (deposit address)

Override PDA

Seeds: ["override", vault_pda, override_nonce]
Purpose: Stores override requests

Fee Treasury PDA

Seeds: ["fee_treasury"]
Purpose: Collects protocol fees

Transaction Flow

Successful Transaction

1. Agent calls execute_agent
2. Protocol verifies agent signer matches vault.agent_signer
3. Check: Is destination whitelisted?
4. Check: Would exceed daily limit?
5. Check: Is vault paused?
6. Calculate fee (0.05%)
7. Transfer SOL from vault authority to destination
8. Transfer fee to treasury
9. Update vault.spent_today
10. Emit TransactionExecuted event

Blocked Transaction (Override Flow)

1. Agent calls execute_agent
2. Policy check fails (not whitelisted or limit exceeded)
3. Transaction reverts with error
4. SDK catches error, calls Guardian API
5. Guardian stores override request
6. Guardian generates Blink URL
7. Owner receives notification
8. Owner approves via Blink
9. Transaction executes

Security Layers

Layer 1: Account Validation

• Verify all account ownership
• Check PDA derivations
• Validate signer authorities

Layer 2: Policy Checks

• Whitelist validation
• Daily limit enforcement
• Pause state check

Layer 3: Arithmetic Safety

• Checked addition/subtraction
• Overflow protection
• Underflow prevention

Layer 4: Fee Collection

• Mandatory 0.05% fee
• Atomic with transfer
• Cannot be bypassed