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Senay Yakut
Senay Yakut

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Agent-402

Building Agent-402: Cryptographically-Signed AI Agents for Regulated Finance

We built infrastructure that lets AI agents work in regulated industries (finance, healthcare, legal) by adding cryptographic signatures, immutable audit trails, and deterministic replay.

🌐 Live Demo: https://agent402.ainative.studio

💻 GitHub: https://github.com/AINative-Studio/Agent-402


The Problem Nobody's Solving

AI agents are everywhere. ChatGPT, AutoGPT, autonomous trading bots—they're powerful and getting smarter every day.

But they can't work in finance. Or healthcare. Or legal. Or any regulated industry.

Why?

Because they're black boxes:

  • ❌ No cryptographic verification
  • ❌ No audit trails
  • ❌ Can't prove what they did
  • ❌ Can't replay decisions
  • ❌ No compliance architecture

A financial regulator asks: "Prove your AI agent made this trade for legitimate reasons."

Current answer: "Uhh... trust us?"

That doesn't fly in regulated industries.

This blocks billions of dollars in AI value from finance, healthcare, legal, and government sectors.


What We Built

Agent-402 is infrastructure for auditable, compliant autonomous agents.

Architecture Overview

┌─────────────────────────────────────────────┐
│           CrewAI Agent System               │
│  ┌──────────┐ ┌──────────┐ ┌──────────┐   │
│  │ Analyst  │ │Compliance│ │Transaction│   │
│  │  Agent   │ │  Agent   │ │   Agent   │   │
│  └────┬─────┘ └────┬─────┘ └────┬──────┘   │
└───────┼────────────┼────────────┼───────────┘
        │            │            │
        └────────────┴────────────┘
                     ↓
        ┌────────────────────────┐
        │   x402 Signing Layer   │
        │  (Cryptographic Sigs)  │
        └───────────┬────────────┘
                    ↓
        ┌────────────────────────┐
        │  Circle Programmable   │
        │       Wallets          │
        └───────────┬────────────┘
                    ↓
        ┌────────────────────────┐
        │    Arc Network (L1)    │
        │  (USDC Settlement <1s) │
        └───────────┬────────────┘
                    ↓
        ┌────────────────────────┐
        │   ZeroDB Ledgers       │
        │  (Immutable Audit Trail)│
        └────────────────────────┘
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Core Components

  1. x402 Protocol - Cryptographically signed requests
  2. Circle Arc Network - Blockchain settlement layer
  3. Circle Wallets - Programmable agent treasuries
  4. CrewAI - Multi-agent orchestration
  5. ZeroDB - Persistent memory & audit ledgers

Technical Deep Dive

1. Cryptographic Signing with x402

Every agent request is cryptographically signed before execution:

from cryptography.hazmat.primitives import hashes, serialization
from cryptography.hazmat.primitives.asymmetric import padding
import base64
import json

def sign_request(payload: dict, private_key) -> str:
    """
    Sign an agent request with private key
    Returns base64-encoded signature
    """
    # Serialize payload deterministically
    message = json.dumps(payload, sort_keys=True).encode()

    # Sign with RSA-PSS
    signature = private_key.sign(
        message,
        padding.PSS(
            mgf=padding.MGF1(hashes.SHA256()),
            salt_length=padding.PSS.MAX_LENGTH
        ),
        hashes.SHA256()
    )

    return base64.b64encode(signature).decode()

def verify_signature(payload: dict, signature: str, public_key) -> bool:
    """
    Verify request signature
    """
    try:
        message = json.dumps(payload, sort_keys=True).encode()
        sig_bytes = base64.b64decode(signature)

        public_key.verify(
            sig_bytes,
            message,
            padding.PSS(
                mgf=padding.MGF1(hashes.SHA256()),
                salt_length=padding.PSS.MAX_LENGTH
            ),
            hashes.SHA256()
        )
        return True
    except Exception:
        return False
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Why this matters:

  • Every agent action has a cryptographic signature
  • Can prove WHO authorized WHAT action WHEN
  • Non-repudiable (agent can't deny it did something)

2. Circle Wallets Integration

Each agent gets its own programmable wallet:

import requests
import os

CIRCLE_API_KEY = os.getenv("CIRCLE_API_KEY")
CIRCLE_API_URL = "https://api.circle.com/v1"

def create_agent_wallet(agent_id: str) -> dict:
    """
    Create a developer-controlled wallet for an agent
    """
    response = requests.post(
        f"{CIRCLE_API_URL}/wallets",
        headers={
            "Authorization": f"Bearer {CIRCLE_API_KEY}",
            "Content-Type": "application/json"
        },
        json={
            "idempotencyKey": f"agent-{agent_id}-{int(time.time())}",
            "walletSetId": os.getenv("WALLET_SET_ID"),
            "metadata": {
                "agent_id": agent_id,
                "created_at": datetime.utcnow().isoformat()
            }
        }
    )

    return response.json()

# Create wallets for each agent
analyst_wallet = create_agent_wallet("analyst-001")
compliance_wallet = create_agent_wallet("compliance-001")
transaction_wallet = create_agent_wallet("transaction-001")
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Agent treasury management:

  • Each agent has its own USDC balance
  • Can track spending per agent
  • Policy-governed (e.g., max $1000/day per agent)

3. Arc Network Settlement

Transactions settle on Arc blockchain in sub-second time:

from web3 import Web3

# Connect to Arc Network
ARC_RPC = "https://rpc.arc.network"
web3 = Web3(Web3.HTTPProvider(ARC_RPC))

# USDC is native gas on Arc
USDC_ADDRESS = "0x..." # Arc USDC contract

def execute_payment(from_wallet: str, to_address: str, amount_usdc: float) -> str:
    """
    Execute USDC payment on Arc Network
    Returns transaction hash
    """
    # Convert USDC amount to smallest unit (6 decimals)
    amount_wei = int(amount_usdc * 10**6)

    # Build transaction
    tx = {
        'from': from_wallet,
        'to': USDC_ADDRESS,
        'value': 0,
        'gas': 100000,
        'gasPrice': web3.eth.gas_price,
        'nonce': web3.eth.get_transaction_count(from_wallet),
        'data': encode_transfer(to_address, amount_wei)
    }

    # Sign and send
    signed_tx = web3.eth.account.sign_transaction(tx, private_key)
    tx_hash = web3.eth.send_raw_transaction(signed_tx.rawTransaction)

    return tx_hash.hex()

def verify_settlement(tx_hash: str) -> bool:
    """
    Verify transaction was successful on Arc
    """
    receipt = web3.eth.get_transaction_receipt(tx_hash)
    return receipt['status'] == 1
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Why Arc Network:

  • USDC as native gas (no ETH needed)
  • Sub-second finality
  • Predictable fees
  • Built for stablecoin commerce

4. Immutable Audit Trail

Every action is logged to ZeroDB:

from zerodb_client import ZeroDBClient

db = ZeroDBClient(
    api_key=os.getenv("ZERODB_API_KEY"),
    project_id=os.getenv("PROJECT_ID")
)

def log_agent_action(
    agent_id: str,
    action_type: str,
    payload: dict,
    result: dict,
    signature: str
):
    """
    Store agent action in immutable ledger
    """
    entry = {
        "agent_id": agent_id,
        "timestamp": datetime.utcnow().isoformat(),
        "action_type": action_type,
        "payload": payload,
        "result": result,
        "signature": signature,
        "tx_hash": result.get("tx_hash"),
        "arc_block": result.get("block_number")
    }

    # Store with vector embedding for semantic search
    db.store(
        collection="agent_actions",
        data=entry,
        text=f"{action_type}: {json.dumps(payload)}"
    )

    return entry

# Example usage
log_agent_action(
    agent_id="transaction-001",
    action_type="usdc_transfer",
    payload={"to": "0x...", "amount": 100.00},
    result={"tx_hash": "0x...", "block_number": 12345},
    signature="base64_signature_here"
)
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Audit capabilities:

  • Query any agent's history
  • Prove what happened when
  • Replay entire workflows
  • Generate compliance reports

Real-World Use Cases

1. Autonomous Trading (Fintech)

from crewai import Agent, Task, Crew

# Define agents
analyst = Agent(
    role="Market Analyst",
    goal="Analyze market conditions and identify opportunities",
    tools=[market_data_tool, sentiment_analysis_tool]
)

compliance = Agent(
    role="Compliance Officer",
    goal="Ensure all trades meet regulatory requirements",
    tools=[kyc_check_tool, aml_screening_tool, risk_assessment_tool]
)

trader = Agent(
    role="Transaction Agent",
    goal="Execute approved trades with x402 signing",
    tools=[x402_signing_tool, arc_settlement_tool]
)

# Orchestrate workflow
crew = Crew(
    agents=[analyst, compliance, trader],
    tasks=[analyze_task, compliance_task, trade_task],
    process="sequential"
)

# Every step is signed and auditable
result = crew.kickoff()
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Compliance benefits:

  • Full audit trail of decision process
  • Can prove compliance checks were performed
  • Deterministic replay for investigations
  • Cryptographically verifiable

2. Clinical Decision Support (Healthcare)

# AI agent analyzes patient data
clinical_agent = Agent(
    role="Clinical Analyst",
    goal="Analyze patient data and recommend treatments",
    tools=[medical_kb_tool, drug_interaction_tool]
)

# Every recommendation is:
# 1. Cryptographically signed by agent
# 2. Stored in immutable ledger
# 3. Can be replayed to show reasoning
# 4. HIPAA-compliant audit trail

recommendation = clinical_agent.execute(patient_data)
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3. Contract Analysis (Legal)

# AI agent reviews legal contracts
legal_agent = Agent(
    role="Contract Analyzer",
    goal="Identify risks and flag issues in contracts",
    tools=[legal_kb_tool, precedent_search_tool]
)

# Benefits:
# - Provable AI analysis
# - Can demonstrate to court
# - Full audit trail
# - Deterministic results
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Results & Performance

Speed

  • ⚡ Transaction settlement: <1 second on Arc
  • ⚡ Agent decision time: 2-5 seconds
  • ⚡ Signature verification: <100ms

Security

  • 🔒 RSA-2048 signatures (industry standard)
  • 🔒 Immutable ledgers (can't modify history)
  • 🔒 On-chain verification (trustless)

Compliance

  • ✅ 100% audit coverage
  • ✅ Cryptographically verifiable
  • ✅ Deterministically replayable
  • ✅ Non-repudiable actions

Try It Yourself

Live Demo

🌐 https://agent402.ainative.studio

Quick Start (Local)

# Clone repository
git clone https://github.com/SenayYakut/Agent-402
cd Agent-402

# Install dependencies
pip install -r requirements.txt

# Set up environment
cp .env.example .env
# Add your API keys:
# - CIRCLE_API_KEY
# - ZERODB_API_KEY
# - ARC_RPC_URL

# Run demo
python scripts/run_demo.py
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Example Output

🚀 Starting Agent-402 Demo

✅ Created analyst wallet: 0x1234...
✅ Created compliance wallet: 0x5678...
✅ Created transaction wallet: 0x9abc...

📊 Analyst Agent: Analyzing market conditions...
   → Opportunity identified: BTC/USDC arbitrage

🔍 Compliance Agent: Running checks...
   → KYC: PASSED
   → AML: PASSED
   → Risk score: LOW

💰 Transaction Agent: Executing trade...
   → Signed with x402: sig_abc123...
   → Submitted to Arc: tx_0xdef456...
   → Confirmed in block: 12345

✅ Trade complete!
📝 Audit entry: https://agent402.ainative.studio/audit/xyz789

⏱️  Total time: 3.2 seconds
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What's Next

Short Term

  • [ ] Add multi-party signing (requires 2+ agents to approve)
  • [ ] Integration with more compliance APIs
  • [ ] Dashboard for monitoring agent activity
  • [ ] More agent templates (DeFi, healthcare, legal)

Long Term

  • [ ] Agent marketplace (deploy pre-built compliant agents)
  • [ ] Cross-chain support (beyond Arc)
  • [ ] Enterprise features (SSO, custom policies)
  • [ ] Regulatory reporting automation

Technical Stack Summary

Component Technology Purpose
Agent Orchestration CrewAI Multi-agent coordination
Signing x402 Protocol Cryptographic request signing
Settlement Circle Arc Network Blockchain + USDC
Wallets Circle Programmable Wallets Agent treasuries
Memory ZeroDB Persistent storage
API FastAPI HTTP server
Language Python 3.11+ Backend logic

Why This Matters

Current state:

  • AI agents are powerful
  • But can't work in regulated industries
  • Compliance is the bottleneck

With Agent-402:

  • Agents can be audited
  • Actions are provable
  • Regulators can verify
  • AI can finally work in finance, healthcare, legal

This unlocks billions in AI value that's currently blocked by compliance concerns.


Links & Resources

Open source (MIT License)

Contributions welcome! ⭐


Discussion

What compliance challenges are you facing with AI systems?

Drop a comment below! I'd love to hear about:

  • Industries where you need auditable AI
  • Specific compliance requirements
  • Features that would make this more useful
  • Questions about the architecture

Let's build the future of compliant AI together! 🚀


Tags

ai #fintech #blockchain #compliance #python #opensource #agents #cryptocurrency #machinelearning #automation

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