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Audit score 70

usability-testing

refoundai/lenny-skills

Conduct effective usability testing to validate concepts and uncover user friction before building.

What is usability-testing?

This skill helps you plan and execute usability tests using frameworks from 11 product leaders. Use it when validating product concepts, optimizing user experience, designing prototype validation, or understanding why users struggle with your product.

Clarify testing goals—whether validating concepts, finding friction points, or optimizing conversion
Choose appropriate test fidelity from Wizard of Oz tests, fake doors, prototypes, or production testing
Design tests by recruiting users, creating scenarios, and identifying what to observe
Guide iteration planning so findings flow back into product development
Identify common testing mistakes like single-design testing or building before validating

How to install usability-testing

npx skills add https://github.com/refoundai/lenny-skills --skill usability-testing

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How to use usability-testing

1.Clarify your testing goal: are you validating a concept, finding friction, or optimizing conversion?
2.Choose the right test fidelity—fake doors and Wizard of Oz for early validation, prototypes or production for optimization
3.Design your test by recruiting unbiased users, creating realistic scenarios, and planning what to observe
4.Run the test with small samples (as few as 10 users) and watch directly rather than relying on surveys
5.Involve cross-functional team members (engineers, designers, PMs) to observe and react live
6.Document findings and plan how results will flow back into your development process

Use cases

Good for

Validate a new feature concept with fake door or Wizard of Oz tests before engineering investment
Run small-sample tests (10 random users) to identify core usability friction points
Compare multiple design options to measure which drives intended user behavior
Optimize conversion by testing micro-level changes like button copy and CTA wording
Conduct cross-functional usability sessions with PMs, engineers, and designers observing live

Who it's for

Product managers planning user validation
Designers optimizing user experience and interface clarity
Founders validating product-market fit
Growth teams optimizing conversion funnels
Engineering teams building features based on user feedback

usability-testing FAQ

How many users do I need for usability testing?

Small samples reveal big friction—as few as 10 random people can provide astute, representative feedback that identifies core product issues.

Should I test one design or multiple options?

Always present multiple options and measure relatively which drives intended behavior. Single-design testing is ineffective for predicting actual user behavior.

When should I use fake door or Wizard of Oz tests?

Use them early to validate core value propositions before writing production code. These methods let you fake the feature with humans performing the task behind the scenes.

How do I overcome my own bias about my product?

Directly observe users interacting with your product without guidance. You tend to overrate how intuitive your product is; watching others reveals real friction you miss.

What should I do with usability testing findings?

Plan how findings flow back into development. Even micro-level changes (7 characters, button labels) can have massive business impact—don't dismiss small issues.

Full instructions (SKILL.md)

Source of truth, from refoundai/lenny-skills.

name: usability-testing description: Help users conduct effective usability testing. Use when someone is planning user tests, designing prototype validation, preparing usability studies, or trying to understand why users struggle with their product.

Usability Testing

Help the user conduct effective usability testing using frameworks and insights from 11 product leaders.

How to Help

When the user asks for help with usability testing:

Clarify the goal - Determine if they're validating a concept, finding friction points, or optimizing conversion
Choose the right fidelity - Help them select between Wizard of Oz tests, fake doors, prototypes, or production testing
Design the test - Guide them on recruiting users, creating scenarios, and what to observe
Plan for iteration - Discuss how findings will flow back into the product development process

Core Principles

Fake it before you build it

Itamar Gilad: "Initially you fake it - fake door test, smoke test, Wizard of Oz tests. We showed the tabbed inbox working to people, but it wasn't really Gmail, it was just a facade." Validate core value propositions before writing production code using faked versions where humans perform the automated task behind the scenes.

Small samples reveal big friction

Melanie Perkins: "It's amazing how you can find 10 random people on the internet and they can give such astute feedback that's so representative for such a large number of people." Run tests with as few as 10 random people to identify core product issues.

Watch users, don't just ask them

Uri Levine: "Simply watch users and see what they're doing. If they're not doing what you expect, then ask them why." Direct observation reveals behaviors and needs that surveys miss. Ask 'why' when users deviate from the expected path.

Test multiple options, not one

Kristen Berman: "We never do a UX study where we're just showing people one thing. We always present multiple options and relatively look for which one drives the intended behavior." Single-design testing is ineffective for predicting behavior.

Overcome creator bias

Guillermo Rauch: "You tend to overrate how well your products work. It's very important to give your product to another person and watch them interact with it." Directly observing users helps overcome the tendency to think your product is more intuitive than it is.

Micro-level testing drives millions

Judd Antin: "We changed seven characters and made Airbnb millions of dollars because we found out the button felt scary." Don't dismiss usability testing as junior work; finding scary or confusing CTAs can massively impact conversion.

Progress through testing stages

Itamar Gilad: "Mid-level tests are about building a rough version - early adopter programs, alphas, longitudinal user studies, and fish food (testing on your own team)." Use a progression from fish fooding to dogfooding to alphas to increase confidence iteratively.

Make testing a team sport

Noah Weiss: "We had PMs, engineers, designers, and the user researcher all in one Slack thread live, responding and reacting to the usability session." Increase engagement by having cross-functional teams live-react to sessions in shared chat threads.

Questions to Help Users

"What specific behavior are you trying to observe or validate?"
"Do you need to validate the concept (use fake doors) or optimize the execution (use the real product)?"
"How will you recruit users who have 'zero skin in the game' for honest feedback?"
"Are you testing one option or multiple options to compare?"
"What will you do with the findings - how will they flow back into development?"
"Who else on the team should observe these sessions?"

Common Mistakes to Flag

Testing only one design - Present multiple options to measure relative performance
Building before validating - Use Wizard of Oz or fake door tests before writing production code
Relying on internal intuition - Employees are too familiar with the product to spot real user friction
Ignoring micro-level issues - Small copy changes and button labels can have massive business impact
Testing in isolation - Bring engineers and designers into sessions to build shared understanding