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Posted on • Edited on • Originally published at idavidov.eu

🚀 How to Use AI for Test Case Generation: A Practical Guide to Empower Your QA Team

In the world of software development, quality assurance (QA) is the bedrock of user trust. Yet, the traditional process of designing test cases is notoriously demanding. It's a time-consuming, manual effort that, despite our best intentions, often leaves gaps—especially around those tricky edge cases. This bottleneck doesn't just slow down releases; it inflates costs and risks letting critical bugs slip into production.

But what if we could change that? What if we could empower every QA engineer to generate comprehensive, high-quality test suites in a fraction of the time?

Enter Generative AI. By leveraging Large Language Models (LLMs), QA teams can now automate the initial, and often most tedious, phase of test creation. This isn't about replacing human expertise; it's about augmenting it. It’s about turning a multi-day task into a minutes-long collaborative effort between engineer and AI, delivering a tangible Return on Investment (ROI) that leadership can't ignore.

✅ The Benefits: More Than Just Speed

Integrating AI into the QA process offers a trifecta of benefits that resonate from the individual engineer to the CTO.

  • Massive Time Savings: The most immediate ROI is the dramatic reduction in time spent writing tests. Industry reports suggest AI can cut test cycle times by up to 60%. By automating the initial draft, engineers are freed from the manual grind and can focus on higher-value tasks like exploratory testing, strategy, and analyzing complex results.
  • Increased Test Coverage: AI excels at identifying permutations and edge cases that are easy for humans to overlook. This leads to a more robust test suite, catching more defects early. Studies show this proactive approach can decrease post-release defects by 30-50%, directly lowering the cost of quality.
  • Empowered Engineering Teams: AI acts as a "senior partner" for every QA engineer. A junior team member can produce a foundational test suite with the breadth of a seasoned expert, while senior members can use the AI-generated output as a checklist to validate their own strategies, ensuring nothing is missed. This up-levels the entire team's capability.

🔴🔴🔴Next Article will dive deep into different research articles to defend the thesis with evidences🔴🔴🔴

🤔 Potential Pitfalls: The Indispensable Human Element

While the benefits are compelling, adopting AI isn't a "set it and forget it" solution. It's a powerful co-pilot, not an autopilot.

The primary pitfall is over-reliance. An LLM lacks true business context and can sometimes "hallucinate" or misinterpret a requirement. It provides a highly educated first draft, but it is not the final authority.

This is where the core principle of this new workflow comes in: The QA engineer is, and always will be, fully responsible for the final test suite. The AI-generated output must be critically reviewed, verified, and refined by a human expert. The engineer's role evolves from a manual author to a strategic editor and validator, using their domain knowledge to correct, enhance, and approve the AI's suggestions.

⚙️ How to Integrate AI into Your QA Workflow

Adopting this technology doesn't require a massive overhaul. It can be integrated into your existing process with a few simple steps:

  1. Develop a Standardized Prompt: Create a master prompt that instructs the AI on the exact format, tone, and structure you need. This ensures consistency across all projects and teams. The case study below uses a perfect example of such a prompt.
  2. Feed the AI Well-Written User Stories: The quality of the AI's output is directly proportional to the quality of its input. Ensure your user stories are clear, detailed, and have well-defined acceptance criteria.
  3. Generate, then Review: The engineer feeds the user story into the standardized prompt. The AI generates the requirements and test cases.
  4. Verify and Refine: The engineer meticulously reviews the output, correcting any errors, filling contextual gaps, and adding any nuanced tests the AI may have missed. The output is a tool, not a deliverable.
  5. Finalize and Automate: Once the human-verified test cases are finalized, they are ready for implementation in an automation framework like Playwright.

🧑🏻‍🔬 Case Study: Generating Tests for a Login Feature

Let's put this theory into practice. We'll use a standardized prompt to ask an LLM to generate requirements and test cases for a common login feature.

The Master Prompt

First, here is the detailed prompt we provide to the AI. It sets clear expectations for the structure and content of the response. Use it out of the box or tailor it to your needs.

As a Senior Automation QA engineer with extensive experience in Test Analysis, Test Planning, and Test Design, generate detailed software requirements and all applicable test cases based on the provided user story. Each user story will come with an ID from the management system (e.g., Redmine, Jira) and should be used as the heading in the format:

User Story #[ID] - [Title]

Your response should be presented in a Markdown ("md") file format using the following structure:

Software Requirements
List detailed software requirements derived from the user story.

Test Cases
Provide a numbered list of test cases with descriptive names that clearly convey the goal of each test. The test cases should cover all major requirements with functional, integration, and end-to-end (E2E) tests, focusing on automation using Playwright.

Unclear Requirements
If there are any aspects of the user story or requirements that are unclear or need further clarification, point them out here. If all requirements are clearly described and there are test cases for every single one, explicitly state that all requirements are well-defined and thoroughly covered by the test cases.

Notes:
The test cases should contain only descriptive names to ensure that QA engineers can understand the goal of each test.
Use consistent formatting and headings to maintain a clear and organized structure.
Number the test cases for better reference and organization.
Ensure that the test cases are suitable for automation using Playwright.
Suggestions:
Since the domain and specific user story will be provided later, keep the prompt flexible to accommodate any context.
When listing software requirements, focus on functional requirements that can be directly tested.
Use bullet points or numbered lists to improve readability within each section.
Maintain a clear distinction between the software requirements and the test cases to ensure clarity.
In the Unclear Requirements section, if no ambiguities are detected, make sure to state that all requirements are clear and fully covered by the test cases.
User Story:
Add the specific user story which should be tested.
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The User Story

Now, we append our specific user story to the prompt.

User Story #PROJ-123 - User Login with Email and Password

Description: As a registered user, I want to be able to log in to my account using my email address and password, so that I can access my personalized dashboard.

Acceptance Criteria:

  • The login page must contain an email input field, a password input field, and a "Login" button.
  • Users must be redirected to their account dashboard upon successful authentication.
  • An error message, "Invalid email or password," must be displayed if the authentication fails.
  • The password field must mask the characters entered.
  • Both the email and password fields are mandatory. An error message should appear if the form is submitted with either field empty.

🤖 The AI-Generated Result

In a matter of seconds, the LLM provides the following output:


Software Requirements

  • The system shall provide a login interface with fields for an email address and a password.
  • The system shall include a "Login" button to initiate the authentication process.
  • The password input field must mask characters to ensure security.
  • The email field must accept validly formatted email addresses.
  • The password field is a mandatory input.
  • The email field is a mandatory input.
  • Upon successful validation of credentials, the system shall redirect the user to their account dashboard.
  • Upon failed validation of credentials, the system shall display the specific error message: "Invalid email or password."
  • The system shall display a validation error if the login form is submitted with an empty email field.
  • The system shall display a validation error if the login form is submitted with an empty password field.

Test Cases

Functional Tests:

  1. Verify that a user can successfully log in with a valid email and password and is redirected to the dashboard.
  2. Verify that an error message "Invalid email or password." is displayed when logging in with a valid email but an incorrect password.
  3. Verify that an error message "Invalid email or password." is displayed when logging in with an invalid email and a valid password.
  4. Verify that an error message "Invalid email or password." is displayed when logging in with an unregistered email address.
  5. Verify that an error message is displayed when attempting to log in with an empty email field.
  6. Verify that an error message is displayed when attempting to log in with an empty password field.
  7. Verify that an error message is displayed when attempting to log in with both email and password fields empty.
  8. Verify that the password field input is masked (e.g., appears as dots or asterisks).
  9. Verify that the login button is disabled until both email and password fields are filled (if this is a requirement).
  10. Verify that the login form handles email addresses with various valid formats (e.g., [email protected]).
  11. Verify that login is case-insensitive for the email address field.
  12. Verify that the login is case-sensitive for the password field.

Integration & E2E Tests:

  1. (Integration) Verify that the login API endpoint successfully returns an authentication token upon a successful login request.
  2. (Integration) Verify that the login API endpoint returns a 401 Unauthorized status code for invalid credentials.
  3. (E2E) Perform a full user journey: Navigate to the login page, enter valid credentials, submit the form, verify redirection to the dashboard, and then successfully log out.
  4. (E2E) Attempt to access a protected page (e.g., /dashboard) without being logged in and verify redirection back to the login page.

Unclear Requirements

All requirements provided in the user story are well-defined and have been thoroughly covered by the generated test cases. However, for enhanced robustness, the following could be clarified:

  • Are there any password strength requirements (e.g., minimum length, character types)?
  • Is there an account lockout policy after a certain number of failed login attempts?
  • What is the expected session timeout period after a successful login?

🔍 Analysis of the Result

This AI-generated output is an incredibly strong starting point. It correctly parsed all acceptance criteria, structured them as formal requirements, and created a comprehensive list of 16 test cases. It covers positive paths, negative paths, validation, and even suggests relevant integration and E2E tests suitable for Playwright.

Crucially, it also demonstrates "intelligence" by identifying potential gaps in the requirements—such as account lockout policies and session timeout—that a senior QA engineer would naturally question. But if you take a closer look, you can point out that the password strength is not relevant to login functionality. This is where the human review adds immense value. The QA engineer can now take this output, confirm the answers to the "Unclear Requirements" with the product manager, and have a near-complete test plan in minutes, not days.

🏆 The ROI is Clear

This case study demonstrates a fundamental shift in the QA paradigm. By embracing AI as a collaborative tool, organizations can accelerate their development cycles, improve software quality, and empower their engineers to work more strategically. The future of QA isn't about replacing humans; it's about building a powerful synergy between human intellect and artificial intelligence.

"The first rule of any technology used in a business is that automation applied to an efficient operation will magnify the efficiency. The second is that automation applied to an inefficient operation will magnify the inefficiency." - Bill Gates


🙏🏻 Thank you for reading! Building robust, scalable automation frameworks is a journey best taken together. If you found this article helpful, consider joining a growing community of QA professionals 🚀 who are passionate about mastering modern testing.

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Top comments (3)

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flexidekstop profile image
flexidesktop

Highly recommended !!!Good!

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idavidov13 profile image
idavidov13

Much appreciated!

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jjbb profile image
Jason Burkes

Really interesting approach! Will you be sharing updates or examples of how teams apply this in more complex scenarios? Looking forward to the next article with the research evidence.