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Anjaiah Methuku
Anjaiah Methuku

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How to replace expensive, latency-heavy LLM text outputs with ultra-fast, typed System-1 decisions in Python agentic workflows.

πŸ“Œ Introduction

When building enterprise Agentic AI Workflows, developers almost universally fall into the same trap: using Large Language Models (LLMs) like GPT-4o, Claude 3.5 Sonnet, or Llama 3 to make operational micro-decisions:

  • Should this order be processed via standard fulfillment, local delivery, or flagged for fraud?
  • Is this high-value return eligible for auto-approval?
  • Which regional warehouse should handle this specific SKU combination?

While LLMs excel at creative writing and open-ended text generation, using an autoregressive model for discrete conditional logic introduces severe engineering bottlenecks: 500ms–2500ms latency per node, excessive token costs, schema parsing failures, and uncalibrated confidence metrics.

In this zero-to-hero guide, we will build a complete, production-ready E-Commerce Order Routing & Fraud Mitigation Engine from scratch using Python, LangGraph, and Jevβ€”the breakthrough System-1 decision model by TypeSafe AI.


⚑ System-1 vs. System-2 AI Paradigm

Named after Daniel Kahneman’s cognitive framework (Thinking, Fast and Slow):

  • System 2 (Generative LLMs): Slow, deliberate, sequential reasoning (Chain-of-Thought, token generation).
  • System 1 (Jev Engine): Fast, parallel, intuitive, structured decision-making in a single pass without token generation.
       β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
       β”‚                Incoming Order Payload                  β”‚
       β”‚   (Cart Items, Delivery Address, Customer History)     β”‚
       β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜
                                  β”‚
                                  β–Ό
      β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
      β”‚              Jev (System-1 Decision Node)                β”‚
      β”‚  Evaluates Fulfillment Route, VIP Eligibility, and       β”‚
      β”‚  Fraud Risk Score in parallel (70ms - 150ms)             β”‚
      β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”¬β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜
                                  β”‚
                 β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”Όβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
                 β–Ό                β–Ό                β–Ό
    β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β” β”Œβ”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”
    β”‚ High Risk / Fraudβ”‚ β”‚ Backorder / VIP  β”‚ β”‚ Standard Route   β”‚
    β”‚  (Security Hold) β”‚ β”‚  (Human Review)  β”‚ β”‚  (Auto-Dispatch) β”‚
    β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜ β””β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”€β”˜
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Comparative Breakdown

Metric / Feature Generative LLMs (System 2) Jev by TypeSafe AI (System 1)
Primary Output Unstructured Text / JSON String Pure Typed Decisions & Probabilities
Execution Autoregressive (token-by-token) Non-autoregressive (parallel evaluation)
Latency 800ms – 3000ms 70ms – 200ms
Cost per 1M Decisions ~$15.00 – $30.00 ~$0.042
Schema Integrity Requires Pydantic / JSON Repair Guaranteed by design
Confidence Calibration Uncalibrated (hallucinates certainty) Calibrated ($RLCD$ Probabilities)

πŸ› οΈ The Three Jev Decision Primitives

Jev evaluates three core primitive types simultaneously in a single API execution:

  1. Noul (Boolean / Binary Logic): Evaluates True/False conditions (e.g., Is this user eligible for VIP express dispatch?).
  2. Choice (Categorical Selection): Selects the single best option from up to 255 pre-defined buckets (e.g., Which fulfillment channel should handle this order?).
  3. Score (Ordinal / Numeric Scale): Rates inputs against a defined scale with custom rubric guidance (e.g., Evaluate fraud risk level from 1 to 5).

πŸ—οΈ Architecture: What We Are Building

We will build an automated Smart Retail Order Orchestrator using LangGraph:

  1. Jev Evaluation Node:
    • Evaluates Fulfillment Channel (Choice).
    • Assesses VIP Express Eligible (Noul).
    • Assesses Fraud Risk Score (Score).
  2. Conditional Router Edge:
    • If Fraud Risk Score $\ge 4 \rightarrow$ Fraud Investigation Node.
    • If Confidence Score $< 0.75 \rightarrow$ Manual Operations Review Node.
    • Otherwise $\rightarrow$ Automated Warehouse Routing Node.

πŸš€ Step-by-Step Implementation

Prerequisites & Setup

Install the required dependencies:

pip install typesafe-ai langgraph langchain-core pydantic python-dotenv
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Configure your environment variables (.env):

TYPESAFE_API_KEY="your_typesafe_jev_api_key"
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Step 1: Define Shared State Schema

Create main.py and set up the shared state object using Python's TypedDict:

import os
from typing import TypedDict, Optional
from typesafe import TypeSafeClient

# Initialize TypeSafe Jev Client
client = TypeSafeClient(api_key=os.getenv("TYPESAFE_API_KEY"))

# Define LangGraph State Schema
class OrderState(TypedDict):
    order_id: str
    order_details: str
    fulfillment_channel: Optional[str]
    is_vip_express: Optional[bool]
    fraud_risk_score: Optional[int]
    confidence_score: Optional[float]
    execution_status: Optional[str]
    dispatch_notes: Optional[str]
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Step 2: Build the Jev Decision Node

The Jev node evaluates three distinct conditions in a single pass without token-by-token text generation:

def jev_order_evaluator(state: OrderState) -> OrderState:
    """Uses Jev System-1 to classify fulfillment route, VIP status, and fraud risk in one call."""

    order_context = state["order_details"]

    # Query Jev Engine
    response = client.jev.evaluate(
        state=order_context,
        questions={
            # Primitive 1: Choice
            "fulfillment_channel": {
                "type": "choice",
                "instructions": "Determine the optimal inventory fulfillment channel for this order.",
                "criteria": {
                    "local_store": "Order items are available locally and address is within same ZIP code area.",
                    "regional_hub": "Standard physical goods requiring regional distribution center shipment.",
                    "digital_delivery": "E-books, software keys, gift cards, or purely digital entitlements.",
                    "freight_special": "Heavy bulk items over 70 lbs requiring freight handling."
                }
            },
            # Primitive 2: Noul (Boolean)
            "is_vip_express": {
                "type": "noul",
                "instructions": "Determine if this order qualifies for priority same-day packaging.",
                "criteria": {
                    "true": "Order explicitly specifies express shipping, subscription tier VIP, or perishable goods.",
                    "false": "Standard delivery speeds or non-urgent items."
                }
            },
            # Primitive 3: Score
            "fraud_risk": {
                "type": "score",
                "instructions": "Evaluate potential transaction risk or policy abuse indicator.",
                "legend": {
                    "1": "standard verified purchase pattern",
                    "3": "minor inconsistency in shipping/billing or high order quantity",
                    "5": "flagged stolen card pattern, disposable email, or extreme payment discrepancy"
                }
            }
        }
    )

    # Unpack typed responses
    channel_res = response.answers["fulfillment_channel"]
    vip_res = response.answers["is_vip_express"]
    fraud_res = response.answers["fraud_risk"]

    return {
        **state,
        "fulfillment_channel": channel_res.selected_option,
        "is_vip_express": vip_res.value,
        "fraud_risk_score": fraud_res.score,
        "confidence_score": min(channel_res.confidence, vip_res.confidence)
    }
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Step 3: Define Execution Nodes & Router Logic

from langgraph.graph import StateGraph, END

def fraud_hold_node(state: OrderState) -> OrderState:
    return {
        **state,
        "execution_status": "FLAGGED_FOR_AUDIT",
        "dispatch_notes": f"🚨 High Risk Score ({state['fraud_risk_score']}/5). Payment placed on administrative hold."
    }

def manual_review_node(state: OrderState) -> OrderState:
    return {
        **state,
        "execution_status": "MANUAL_OPS_QUEUE",
        "dispatch_notes": f"⚠️ Low confidence classification ({state['confidence_score']:.2f}). Forwarded to fulfillment manager."
    }

def warehouse_dispatch_node(state: OrderState) -> OrderState:
    channel = state["fulfillment_channel"].upper()
    priority = "EXPRESS" if state["is_vip_express"] else "STANDARD"
    return {
        **state,
        "execution_status": "PROCESSED",
        "dispatch_notes": f"βœ… Order routed to [{channel}] with [{priority}] fulfillment priority."
    }

def route_order(state: OrderState) -> str:
    # 1. Fraud Risk Check
    if state["fraud_risk_score"] and state["fraud_risk_score"] >= 4:
        return "fraud_hold"

    # 2. Confidence Threshold Check (Calibrated Probability)
    if state["confidence_score"] and state["confidence_score"] < 0.75:
        return "manual_review"

    # 3. Standard Path
    return "warehouse_dispatch"
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Step 4: Assemble & Compile the LangGraph Pipeline

workflow = StateGraph(OrderState)

# Add Graph Nodes
workflow.add_node("jev_evaluator", jev_order_evaluator)
workflow.add_node("fraud_hold", fraud_hold_node)
workflow.add_node("manual_review", manual_review_node)
workflow.add_node("warehouse_dispatch", warehouse_dispatch_node)

# Define Entry Point
workflow.set_entry_point("jev_evaluator")

# Add Conditional Routing
workflow.add_conditional_edges(
    "jev_evaluator",
    route_order,
    {
        "fraud_hold": "fraud_hold",
        "manual_review": "manual_review",
        "warehouse_dispatch": "warehouse_dispatch"
    }
)

# Attach Terminal Edges
workflow.add_edge("fraud_hold", END)
workflow.add_edge("manual_review", END)
workflow.add_edge("warehouse_dispatch", END)

# Compile Graph
app = workflow.compile()
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Step 5: Test Execution Runs

if __name__ == "__main__":
    sample_order = {
        "order_id": "ORD-88392",
        "order_details": "Customer ordered 1x Pro Gaming Laptop ($1,800). Shipping address is local store pickup (ZIP 90210). Priority status set to VIP Same-Day.",
        "fulfillment_channel": None,
        "is_vip_express": None,
        "fraud_risk_score": None,
        "confidence_score": None,
        "execution_status": None,
        "dispatch_notes": None
    }

    result = app.invoke(sample_order)

    print("\n--- ORDER PIPELINE RESULTS ---")
    print(f"Fulfillment Channel : {result['fulfillment_channel']}")
    print(f"VIP Express Eligible: {result['is_vip_express']}")
    print(f"Fraud Risk Rating  : {result['fraud_risk_score']}/5")
    print(f"Engine Confidence  : {result['confidence_score']:.2f}")
    print(f"Status             : {result['execution_status']}")
    print(f"Notes              : {result['dispatch_notes']}")
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πŸ“ˆ Performance & Cost Comparison

Metric Generative LLM Node (GPT-4o) Jev System-1 Engine
Average Latency ~1400 ms ~90 ms (~15x Faster)
Cost per 1M Executions ~$18.00 ~$0.042 (~400x Cheaper)
Schema Reliability Susceptible to JSON parsing errors 100% Guaranteed Native Types
Confidence Score Heuristic / Often Overconfident Calibrated Probabilistic Score

🎯 Key Takeaways

  1. Decouple Logic from Text Generation: Reserve LLMs like GPT-4o or Claude for synthesizing text, writing emails, or summarizing documents. Use System-1 decision engines like Jev for routing and classification nodes.
  2. Deterministic Outputs: Jev provides zero-parsing overhead by producing calibrated native types (bool, int, enum) directly.
  3. Calibrated Fallbacks: By pairing Jev's calibrated confidence scores with LangGraph conditional edges, you can implement robust human-in-the-loop triggers whenever uncertainty passes your set threshold.

πŸ”— Related Resources & Further Reading


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