LLM を使用した自律型 AI ワークフローの構築

import json
from typing import Dict, Any

# Mock databases and tools
PURCHASE_DB = {
    "user_123": {"item": "Premium Subscription", "price": 149.00, "days_ago": 12},
    "user_456": {"item": "Basic License", "price": 49.00, "days_ago": 45}
}

class AutonomousRefundAgent:
    def __init__(self):
        self.state: Dict[str, Any] = {
            "step": "INIT",
            "user_id": None,
            "refund_amount": 0.0,
            "policy_passed": False,
            "requires_approval": False,
            "approved": False,
            "response_draft": "",
            "log": []
        }

    def run(self, user_id: str, request_text: str):
        self.state["user_id"] = user_id
        self.state["log"].append(f"Started workflow for user {user_id} with request: '{request_text}'")
        
        while self.state["step"] != "COMPLETE":
            current_step = self.state["step"]
            if current_step == "INIT":
                self._fetch_user_data()
            elif current_step == "VALIDATE_POLICY":
                self._validate_policy()
            elif current_step == "CHECK_APPROVAL":
                self._check_approval_requirements()
            elif current_step == "WAITING_FOR_HUMAN":
                # Pause execution and yield control back to the orchestrator
                self.state["log"].append("Execution paused: waiting for human operator approval.")
                break
            elif current_step == "EXECUTE_REFUND":
                self._execute_refund()
            elif current_step == "DRAFT_RESPONSE":
                self._draft_response()
                
        return self.state

    def _fetch_user_data(self):
        user_id = self.state["user_id"]
        purchase = PURCHASE_DB.get(user_id)
        if not purchase:
            self.state["response_draft"] = "No purchase history found for this user."
            self.state["step"] = "DRAFT_RESPONSE"
            self.state["log"].append("Fetch failed: User not found in database.")
            return

        self.state["refund_amount"] = purchase["price"]
        self.state["purchase_age_days"] = purchase["days_ago"]
        self.state["step"] = "VALIDATE_POLICY"
        self.state["log"].append(f"Fetched purchase data: {purchase}")

    def _validate_policy(self):
        # Business rule: Refunds only allowed within 30 days
        age = self.state["purchase_age_days"]
        if age <= 30:
            self.state["policy_passed"] = True
            self.state["step"] = "CHECK_APPROVAL"
            self.state["log"].append("Policy validation passed (within 30-day window).")
        else:
            self.state["policy_passed"] = False
            self.state["response_draft"] = "Sorry, our policy only allows refunds within 30 days of purchase."
            self.state["step"] = "DRAFT_RESPONSE"
            self.state["log"].append("Policy validation failed: Purchase older than 30 days.")

    def _check_approval_requirements(self):
        # Business rule: Refunds over $100 require human review
        amount = self.state["refund_amount"]
        if amount > 100.0:
            self.state["requires_approval"] = True
            self.state["step"] = "WAITING_FOR_HUMAN"
            self.state["log"].append(f"Refund of ${amount} exceeds limit. Moving to human approval state.")
        else:
            self.state["requires_approval"] = False
            self.state["step"] = "EXECUTE_REFUND"
            self.state["log"].append(f"Refund of ${amount} is within limits. Proceeding to execution.")

    def resume_with_human_decision(self, approved: bool):
        if self.state["step"] != "WAITING_FOR_HUMAN":
            raise ValueError("Agent is not currently waiting for approval.")
        
        self.state["approved"] = approved
        self.state["log"].append(f"Human manager decision received: Approved = {approved}")
        
        if approved:
            self.state["step"] = "EXECUTE_REFUND"
        else:
            self.state["response_draft"] = "Your refund request has been reviewed and declined by a customer service manager."
            self.state["step"] = "DRAFT_RESPONSE"
            
        # Resume the workflow loop
        return self.run(self.state["user_id"], "")

    def _execute_refund(self):
        amount = self.state["refund_amount"]
        # Trigger actual external API call/Stripe integration here
        self.state["log"].append(f"Successfully processed stripe refund for ${amount}.")
        self.state["response_draft"] = f"Your refund request for ${amount} has been successfully processed."
        self.state["step"] = "DRAFT_RESPONSE"

    def _draft_response(self):
        # Prompt LLM to draft a polite, personalized message incorporating response_draft
        self.state["final_message"] = f"Dear Customer,\n\n{self.state['response_draft']}\n\nBest regards,\nGhaznix Support Agent"
        self.state["step"] = "COMPLETE"
        self.state["log"].append("Customer email drafted successfully. Workflow complete.")