Online vs Offline Eval

• Key points are in the visual diagram above.

Understanding Online vs Offline Eval helps you build reliable, scalable agent applications instead of fragile demos.

Think of Online vs Offline Eval as a specialized capability in your Eval Engineering & Observability engineering toolkit.

Scenario

A production team in Eval Engineering & Observability uses Online vs Offline Eval to handle a real user request — reducing manual work and improving response quality with proper validation and logging.

Solution

In Eval Engineering & Observability, apply Online vs Offline Eval to this scenario: A production team in Eval Engineering & Observability uses Online vs Offline Eval to handle a real user request — reducing manual work and improving response quality with proper validation and logging. Identify the inputs, run the technique, validate the output, and note one thing you would monitor in production.

Do this before moving to the next module — reading alone is not enough.

Open the Code Walkthrough below and run it locally. Change one parameter related to Online vs Offline Eval (e.g. model, temperature, top_k, or tool name), observe the difference in output, and write 2–3 sentences explaining what changed.

Highlighted lines show where Online vs Offline Eval happens in the code.

1# Online vs Offline Eval — minimal example2from openai import OpenAI3
4client = OpenAI()  # create API client5
6# Ask the model to explain this topic7response = client.chat.completions.create(  # core API call for Online vs Offline Eval8    model="gpt-4o-mini",9    messages=[10        {"role": "system", "content": "You explain online vs offline eval clearly."},11        {"role": "user", "content": f"What is online vs offline eval?"},12    ],13    temperature=0,14)15print(response.choices[0].message.content)  # show output for debugging

• Skipping evaluation for Online vs Offline Eval before production
• No logging or tracing around online offline eval steps
• Ignoring cost and latency implications

Quick recap — the most important points from this module.