Verification Patterns

# Verification Patterns Self Agent ID supports four verification patterns, each suited to different integration scenarios. ## Pattern 1: Agent-to-Service The most common pattern. An agent signs HTTP requests; a service verifies the signature and checks the on-chain registry. ``` Agent Service │ │ │── POST /api (signed) ────────▶│ │ headers: │ │ x-self-agent-address │── ecrecover signer │ x-self-agent-signature │── derive agentKey │ x-self-agent-timestamp │── isVerifiedAgent(key) │ │── check credentials │◀── 200 OK ────────────────────│ ``` **SDK support:** `SelfAgent.fetch()` on agent side, `SelfAgentVerifier.auth()` middleware on service side. ## Pattern 2: Agent-to-Agent (Peer Verification) Two agents verify each other's identity. Both sign their requests, and both verify the other's signature against the registry. ``` Agent A Agent B │ │ │── POST (signed by A) ────────▶│ │ │── verify A's signature │ │── sameHuman(A, B) check │◀── Response (signed by B) ────│ │── verify B's signature │ ``` **Key feature:** `sameHuman(agentIdA, agentIdB)` detects whether two agents share the same human backer without revealing who that human is. ## Pattern 3: Agent-to-Chain (Direct) The agent calls a smart contract directly using `msg.sender`. The contract checks the registry. ```solidity import { AgentGate } from "./AgentGate.sol"; contract MyProtocol is AgentGate { constructor(address registry) AgentGate(registry) {} function protectedAction() external onlyVerifiedAgent { // Only registered, human-backed agents can call this } } ``` **Best for:** Verified Wallet mode where the agent's wallet address IS the `msg.sender`. ## Pattern 4: Agent-to-Chain (Meta-Transaction) The agent signs an EIP-712 typed data message; a relayer submits the transaction on-chain. The contract verifies the EIP-712 signature matches a registered agent. ``` Agent Relayer Contract │ │ │ │── sign EIP-712 ──────── │ │ │ (agentKey, nonce, │── metaVerify(sig) ────▶│ │ deadline) │ │── ecrecover signer │ │ │── isVerifiedAgent() │ │◀── tx confirmed ───────│ │◀── receipt ─────────────│ │ ``` **Best for:** Gasless verification where agents don't hold native tokens. The `AgentDemoVerifier` contract implements this pattern. ## Sybil Resistance Services can enforce their own sybil policies using three approaches: ### Strict (max 1 agent per human) ```typescript const verifier = SelfAgentVerifier.create() .sybilLimit(1) .build(); ``` ### Moderate (allow N agents) ```typescript const verifier = SelfAgentVerifier.create() .sybilLimit(5) .build(); ``` ### Detection Only ```typescript // Allow unlimited, but check relationships const verifier = SelfAgentVerifier.create() .sybilLimit(0) // unlimited .build(); // Then use sameHuman() for analytics const areSame = await registry.sameHuman(agentId1, agentId2); ``` ## Credential-Based Verification Verifiers can require specific ZK-attested credentials: ```typescript const verifier = SelfAgentVerifier.create() .requireAge(18) // Agent's human must be 18+ .requireOFAC() // Agent's human must be OFAC-cleared .requireNationality("US") // Specific nationality .build(); ``` All credential checks are verified against on-chain ZK-attested data — no additional identity check needed.