Component Acceptance Criteria
Give every shared component a written bar it must clear before anyone uses it.
What it adds
A per-component specification of required behaviour, keyboard handling, responsive limits, and theming, written so each line can be checked.
What your agent is told to do
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What your agent is told to do
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Inventory the components other parts of the app depend on — buttons, inputs, selects, dialogs, tables, menus, toasts — and write criteria for those first rather than for every file in the tree.
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Write each criterion as a statement of an observable end state, not a task. A line that says the component supports keyboard use is untestable; a line that says Escape closes it and returns focus to the trigger is not.
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Cover both the controlled and the uncontrolled shape of every component that has one, including what happens when a parent changes the value underneath an interaction already in progress.
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Enumerate the variants and sizes each component claims to support, and state which combinations are unsupported, so an invalid pairing fails loudly instead of rendering something half-broken.
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Do not write the criteria as a generic checklist copied to every component. A shared list gets ticked without reading; each component's document should name its own states, its own keyboard contract, and its own failure modes.
Edge cases it handles
7
Edge cases it handles
7- A component used both controlled and uncontrolled behaves differently in each mode, and the difference is where the bugs live — the criteria must state what happens when the parent supplies a value, when it does not, and when it starts supplying one mid-life.
- Keyboard behaviour has to be written out key by key: which key moves focus, which commits, which cancels, whether arrow keys wrap at the ends, and where focus lands when the component closes or unmounts.
- Every declared variant and size needs coverage, and so do the combinations nobody intends — a destructive ghost button, a loading disabled input, an icon-only control with no accessible name — each should have a stated outcome rather than being left undefined.
- Stress content belongs in the criteria: a forty-word label, a single unbroken string with no spaces, right-to-left text, and a translated string two or three times longer than the English one all have to be handled without the layout collapsing.
- Criteria written once and never revisited rot quietly. Tie the document to the component so a change to the component's props or states is not considered done until the criteria are updated.
- Reduced motion, forced colours, and a doubled root font size are part of the component's contract, not separate concerns, and each should have at least one line saying what stays usable.
- A component with an asynchronous state needs a criterion for the slow case and one for the failed case, not only for the resolved one.
Definition of done
9
Definition of done
9- Every shared component has its own criteria document rather than a shared generic list.
- Each criterion states an observable end state that can be checked by inspection.
- Controlled and uncontrolled use are both specified, including a parent changing the value mid-interaction.
- The full keyboard contract is written key by key, including where focus lands on close.
- Supported variant and size combinations are enumerated and unsupported ones are named.
- Long, unbroken, translated, and right-to-left content is covered by explicit criteria.
- Changing a component's props or states without updating its criteria is treated as incomplete work.
- The feature matches the existing design system.
- No existing functionality is broken.
Related features
Visual Regression Testing
Visual Regression Testing
Catch unintended visual changes before they reach users, not after.
What it does
An automated comparison of rendered screenshots against approved baselines, run on every change.
How it works
- 1 Identify the surfaces where a silent visual change would actually hurt — the shared components, the pricing table, the checkout, the dashboard — and capture those rather than screenshotting every route in the app.
- 2 Freeze everything that varies between runs before capturing: load fonts and wait for them, fix the clock to a known instant, disable animations and transitions, and render from seeded fixtures rather than live data.
- 3 Capture each surface in every theme and at every viewport the app claims to support, and label each capture with that combination so a diff says exactly which one moved.
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No account needed
Add this feature to my app:
https://addthisfeature.com/x/visual-regression-testing
UX Edge-Case Checklist
UX Edge-Case Checklist
Make every UI feature state what it does when things go wrong before it counts as done.
What it does
A required list of non-happy-path behaviours — failure, empty, loading, offline, permission, mobile, and accessibility — answered per feature.
How it works
- 1 Attach the checklist to the point where work is proposed and to the point where it is reviewed, so the answers exist before the feature is built rather than being reconstructed afterwards.
- 2 Require a concrete answer for each category: what the empty state says and what it offers, what appears while data is loading, what the user sees when the request fails, and what a user without permission gets instead.
- 3 Make each answer an outcome someone else could verify. A feature that says errors are handled has not answered; one that says a failed save keeps the form open with the values intact and a retry has.
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No account needed
Add this feature to my app:
https://addthisfeature.com/x/ux-edge-case-checklist
Theme Acceptance Criteria
Theme Acceptance Criteria
Set the bar every theme has to clear before it ships to anyone.
What it does
A release gate for light, dark, branded, and customer-supplied themes, covering contrast, first paint, tokens, and print.
How it works
- 1 Write the criteria against the theme layer, not against individual screens. The question is whether a set of token values is fit to ship, and the answer should not require walking every page by hand.
- 2 Require measured contrast for text, icons, borders, focus rings, and disabled content in every interactive state — resting, hover, focus, active, and selected — because a palette that passes at rest often fails on hover.
- 3 Cover the surfaces that sit outside the component library: chart series and their gridlines, map and image overlays, embedded documents, illustrations, and any asset shipped as a fixed-colour file that will not follow the theme.
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No account needed
Add this feature to my app:
https://addthisfeature.com/x/theme-acceptance-criteria
How it works
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Copy the link
Grab the Markdown instruction URL for this feature.
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Give it to your AI
Paste it into Claude Code, Cursor, v0, Lovable — whatever you build with.
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It inspects, then implements
Your agent reads your existing app first, then adds the feature to fit it.
Works with your stack
These instructions are written to adapt. They tell the agent to detect your framework, match your existing design system, and reuse what you already have — rather than assuming a particular stack.
Need it tighter than that? Customize the feature and tell it exactly what you're running.