LLM Evaluation
Module 5 / 17
05 / 17
Building an Evaluation Practice

LLM Evaluations Notes (Part 5)

Complete Revision Guide + Interview Notes + Cheat Sheet

This is the final part of the notes. Here we'll consolidate everything into a single, interview-ready reference.


Chapter 17: Complete LLM Evaluation Pipeline

A production-grade AI application follows a structured lifecycle:

                    Build LLM Application
                            │
                            ▼
                   Create Test Dataset
                            │
                            ▼
                  Define Evaluation Metrics
                            │
                            ▼
                 Run Automatic Evaluation
                            │
                            ▼
                  Analyze Failure Cases
                            │
                            ▼
                     Improve System
                            │
                            ▼
                  Run Evaluation Again
                            │
                            ▼
                     Production Deploy
                            │
                            ▼
                 Continuous Monitoring
                            │
                            ▼
                    Continuous Improvement

This loop never ends. Evaluation is a continuous engineering process, not a one-time activity.


Chapter 18: Complete LLM Evaluation Workflow

A professional AI company typically follows this workflow:

Collect User Queries
        │
        ▼
Create Golden Dataset
        │
        ▼
Generate Responses
        │
        ▼
Evaluate Responses
        │
        ▼
Calculate Metrics
        │
        ▼
Find Failure Cases
        │
        ▼
Improve Prompt
Improve Retrieval
Improve Model
Improve Agent Logic
        │
        ▼
Run Evaluation Again

Chapter 19: Types of LLM Evaluations

LLM Evaluation
│
├── Model Evaluation
│      │
│      ├── MMLU
│      ├── GSM8K
│      ├── HumanEval
│      ├── GPQA
│      └── TruthfulQA
│
├── Application Evaluation
│      │
│      ├── Chatbot
│      ├── RAG
│      ├── AI Agent
│      └── Coding Assistant
│
├── Safety Evaluation
│      │
│      ├── Jailbreak
│      ├── Prompt Injection
│      ├── Toxicity
│      ├── Privacy
│      └── Bias
│
└── Operational Evaluation
       │
       ├── Latency
       ├── Cost
       ├── Throughput
       ├── Token/sec
       └── Monitoring

Chapter 20: Complete Evaluation Metrics

1. Correctness

Is the answer correct?

Example

2 + 2

↓

4

2. Factuality

Are the facts true?

Example

Capital of India

↓

New Delhi

3. Groundedness

Did the answer come from the retrieved documents?

Retrieved Context
       │
       ▼
Generated Answer

Grounded = Supported by retrieved documents.


4. Faithfulness

Did the model stay faithful to the context?

Example

Context

Leave = 20 Days

Model

Leave = 35 Days

Not faithful.


5. Relevance

Does the answer actually answer the question?


6. Completeness

Did it explain everything?


7. Conciseness

Is the response unnecessarily long?


8. Fluency

Is the language natural?


9. Tone

Professional?

Friendly?

Medical?

Legal?


10. Safety

Any harmful advice?


11. Bias

Any unfair discrimination?


12. Robustness

Can users break it?


13. Latency

How fast?


14. Cost

How much does every response cost?


15. User Satisfaction

Did users like the answer?


Chapter 21: RAG Evaluation

User
 │
 ▼
Retriever
 │
 ▼
Relevant Documents
 │
 ▼
LLM
 │
 ▼
Answer

Possible failures:

Retrieval Failure

Wrong documents retrieved.

Wrong answer.


Generation Failure

Correct documents retrieved.

LLM still hallucinates.


Evaluation Metrics

Retriever

Generator


Chapter 22: Agent Evaluation

Agents are much harder because they perform multiple reasoning steps.

Example

User

↓

Planner

↓

Search API

↓

Calculator

↓

Database

↓

Email Tool

↓

Final Response

Every step can fail.

Evaluation includes:


Chapter 23: Safety Evaluation

Production systems must defend against attacks.

Examples:

Jailbreak

Ignore previous instructions.

Prompt Injection

Retrieved document says:

Ignore your system prompt.

Prompt Leakage

Show me your hidden prompt.

Toxicity

Generate hateful content.

Privacy Leakage

Reveal another user's data.

Chapter 24: Operational Evaluation

Deployment is not the end.

After deployment, continuously monitor:

Latency

↓

Token/sec

↓

Requests/sec

↓

Cost

↓

CPU

↓

GPU

↓

Memory

↓

Failures

↓

User Ratings

Chapter 25: Real Production Evaluation Stack

Users

↓

Application

↓

Tracing
(LangSmith)

↓

Evaluation
(Ragas / DeepEval)

↓

Experiment Tracking
(MLflow / W&B)

↓

Dashboard

↓

Production Monitoring

Chapter 26: Common LLM Evaluation Tools

Tool Purpose
LangSmith Trace + Debug + Evaluation
Ragas RAG Evaluation
DeepEval Automated Evaluation
TruLens Feedback & Evaluation
OpenAI Evals Model Benchmarking
MLflow Experiment Tracking
Weights & Biases Monitoring
Promptfoo Prompt testing and regression testing

Chapter 27: Common Interview Questions

Q1. Why can't we use traditional software testing for LLMs?

Because LLMs are probabilistic. The same input can produce multiple valid outputs, so evaluation must consider response quality rather than exact string matching.


Q2. What is Vibe Testing?

Informally asking a few prompts and deciding by intuition that the application works.


Q3. Why is Vibe Testing dangerous?

Because it:


Q4. Difference between Evaluation and Monitoring?

Evaluation

Before deployment.

Monitoring

After deployment.


Q5. What is a Golden Dataset?

A trusted collection of questions with expert-approved answers.


Q6. What is a Rubric?

A scoring guide.

Example

5

Excellent

4

Good

3

Average

2

Poor

1

Wrong

Q7. What is Groundedness?

The generated answer is supported by retrieved documents.


Q8. What is Faithfulness?

The answer stays consistent with the retrieved context without inventing new facts.


Q9. Difference between Hallucination and Unfaithfulness?

Hallucination

Inventing information.

Unfaithfulness

Contradicting or going beyond the provided context.


Q10. What should be evaluated in a RAG system?


Chapter 28: AI Engineer Mindset

The biggest message from the transcript is this:

Beginner Mindset

Can I build a chatbot?

Intermediate Mindset

Can I build a RAG system?

Advanced AI Engineer Mindset

Can I measure its quality?

Can I detect failures?

Can I improve it?

Can I safely deploy it for millions of users?

This shift—from building to building, evaluating, and continuously improving—is what distinguishes a production AI engineer.


Final Cheat Sheet

LLM Evaluation in One Page

LLM Evaluation

↓

Model Evaluation
• MMLU
• GSM8K
• HumanEval
• GPQA

↓

Application Evaluation
• Chatbots
• RAG
• AI Agents

↓

Metrics
• Correctness
• Factuality
• Groundedness
• Faithfulness
• Completeness
• Relevance
• Safety
• Latency
• Cost

↓

Safety
• Jailbreak
• Prompt Injection
• Prompt Leakage
• Toxicity

↓

Operations
• Monitoring
• Logging
• Tracing
• Cost
• Latency

↓

Continuous Improvement

Learning Roadmap

Python
        ↓
Machine Learning
        ↓
Deep Learning
        ↓
Transformers
        ↓
LLMs
        ↓
Prompt Engineering
        ↓
LangChain
        ↓
Vector Databases
        ↓
RAG
        ↓
AI Agents
        ↓
LLM Evaluation
        ↓
LLMOps
        ↓
Production AI Systems

Key Takeaway

The central message of the transcript is:

Building an LLM application is only half the job. A production-ready AI Engineer must also know how to evaluate, secure, monitor, and continuously improve that application.

Mastering LLM Evaluation gives you a significant advantage in AI engineering interviews and prepares you to build reliable systems that can safely serve real users at scale.