LLM Evaluations: Why They Matter
Published: 2024-06-04 16:25:58

When building applications powered by large language models, it's easy to get excited about the rapid prototyping capabilities. However, as you move beyond the initial prototype phase, you'll encounter various challenges that can impact the stability and reliability of your app. To address these issues and ensure a robust LLM-based application, implementing a comprehensive evaluation and testing strategy is crucial.

## The Challenges of LLM-based Apps:
1. Hallucinations: LLMs can generate outputs that seem plausible but are factually incorrect or inconsistent with reality.
2. Factuality problems: LLMs may provide inaccurate information or make mistakes in their responses.
3. Steering to weird directions: LLMs can sometimes generate inappropriate or irrelevant content.
4. Hacking attempts: Malicious users may try to exploit vulnerabilities in LLMs to manipulate their behavior.
5. Reputational and legal risks: Inaccurate or offensive outputs from LLMs can damage your brand reputation and potentially lead to legal issues.

## The Importance of LLM Evaluations:
To mitigate these challenges and ensure the stability of your LLM-based app, implementing a robust evaluation and testing process is essential. Here's how you can approach it:

1. Record all data: Start by logging all interactions with your LLM-based app. This includes user inputs, generated outputs, and any relevant metadata.

2. Flag bad answers: Manually review the logged data and flag any instances of hallucinations, factual errors, inappropriate content, or other problematic outputs.

3. Create test datasets: Use the flagged bad answers to create test datasets that cover a wide range of potential issues. These datasets will serve as a reference for evaluating the performance of your LLM.

4. Implement automated tests: Develop automated tests that compare the LLM's outputs against the expected results defined in your test datasets. This allows you to quickly identify regressions and ensure the stability of your app as you iterate on the LLM's prompts and configurations.

5. Leverage LLMs as judges: Utilize separate LLMs as "judges" to evaluate the quality and appropriateness of the outputs generated by your primary LLM. This adds an extra layer of validation and helps catch issues that may be missed by automated tests.

6. Perform post-processing checks: Implement post-processing checks on the LLM's outputs to detect and handle problematic content, such as prompt injection attempts, profanity, or outputs that violate predefined constraints.

7. Continuously iterate and expand: As you discover new issues or edge cases, update your test datasets and automated tests accordingly. Continuously monitor the performance of your LLM-based app and iterate on the evaluation process to ensure ongoing stability and reliability.


Building stable and reliable LLM-based applications requires a proactive approach to evaluation and testing. By recording data, flagging bad answers, creating test datasets, implementing automated tests, leveraging LLMs as judges, performing post-processing checks, and continuously iterating, you can effectively identify and address the challenges associated with LLMs. This comprehensive evaluation strategy will help you deliver a high-quality and trustworthy application to your users.


## Do you want to know how to implement these LLM evaluation techniques in your own projects?

Let me know in the comments below, and I'll be happy to provide more detailed guidance and share some practical examples to help you get started!