Transition Consistency
Decide once what animates, for how long, and when motion is left out entirely.
What it adds
A single set of rules governing which properties may be transitioned across the app, and which interactions deliberately have no motion at all.
What your agent is told to do
5
What your agent is told to do
5-
1
Audit the app for every transition currently in place and record what it animates. Anything transitioning a property that forces the browser to recompute layout is the first thing to replace.
-
2
Restrict transitions to properties that can be composited — opacity and transforms — and express size and position changes that way rather than animating width, height, or offsets directly.
-
3
Write down the interactions that must never animate: value updates in a table the user is scanning, error messages appearing, and anything that would delay the confirmation of an action.
-
4
Make motion decorative rather than load-bearing. The state change lands immediately and the animation describes it afterwards, so a user on reduced motion or a slow device sees the same result at the same moment.
-
5
Do not implement this by adding a blanket transition to every element. A universal rule catches things it was never meant to, and produces elements that visibly drift when they should appear instantly.
Edge cases it handles
7
Edge cases it handles
7- Transitions on properties that trigger layout or paint on every frame will stutter on modest hardware and on long lists; move them to transforms and opacity or drop them.
- Motion must never sit between the user and the result of their action — a button that waits for an animation to finish before committing feels broken regardless of how good the animation is.
- Rapid toggling must be handled explicitly. Clicking a disclosure five times quickly should end in the correct final state, with each transition picking up from wherever the last one reached.
- When the user has asked for reduced motion the app must honour it at the level of the whole system, and the layout must be identical with motion on and off.
- Durations and curves themselves are owned by Motion Token System; this entry decides which properties are eligible and where motion is omitted, and should reference those tokens rather than defining new values.
- Transitions inside a virtualised or paginated list must not fire when rows are recycled, or scrolling produces a wall of animation.
- An element that is animating must still be clickable and focusable throughout, not inert until the motion settles.
Definition of done
8
Definition of done
8- Transitions are limited to compositable properties across the whole app.
- No interaction waits on an animation before its result is committed.
- Rapid repeated toggling always settles in the correct final state.
- Reduced-motion preferences are honoured system-wide, with identical layout in both modes.
- Timing values come from the shared motion tokens rather than being defined locally.
- Recycled rows in long lists do not replay entrance transitions.
- The feature matches the existing design system.
- No existing functionality is broken.
Related features
Z-Index Registry
Z-Index Registry
Keep every stacking value in one file so nobody has to guess a bigger number.
What it does
A single source of named z-index tokens, with reserved ranges per layer and a check that blocks raw values.
How it works
- 1 Find every z-index in the codebase, including inline styles and values buried in third-party overrides, and list them with the component that owns each. The count is usually higher than anyone expects and several will be arbitrary large numbers.
- 2 Reserve a range for each layer rather than assigning single values, so a new dropdown can slot between existing ones without renumbering everything above it. Leave real gaps between ranges.
- 3 Name each token after the layer it belongs to and derive the ordering from Elevation Layer Map. That feature decides what covers what; this one holds the numbers and stops them being invented locally.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/z-index-registry
Spacing Scale
Spacing Scale
Reduce the app's spacing to a small set of steps that repeat across every surface.
What it does
A named spacing scale covering gaps, padding, and section rhythm, with every existing value in the app mapped onto it.
How it works
- 1 Collect every spacing value currently in the codebase and count how often each appears. The result is usually a handful of genuine intentions surrounded by dozens of near-misses that were nudged once and never revisited.
- 2 Define a scale that is fine at the small end, where control padding lives, and coarse at the large end, where section separation lives. A linear scale gives too many indistinguishable large steps and too few small ones.
- 3 Separate the tokens used inside a component from the ones used between components and between page sections, and name them so the difference is obvious. The same number serving both purposes means a change to button padding also changes the gap between sections.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/spacing-scale
Shadow Scale
Shadow Scale
Replace ad hoc shadows with a small set tied to what each surface actually is.
What it does
A fixed ladder of shadow tokens, each named for an elevation role rather than a blur radius.
How it works
- 1 Collect every shadow currently declared anywhere in the app and group them by what they sit on — a resting card, a hovered card, a dropdown, a dialog, a toast. Most apps have a dozen near-identical values that collapse into four or five roles.
- 2 Name each step for its role, not its appearance. A token called menu tells the next person which surfaces may use it; a token called shadow-md-2 does not.
- 3 Use a single light source for the whole scale, so offset, blur, and spread grow together as elevation rises. Two shadows lit from different directions on the same screen read as a rendering bug.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/shadow-scale
How it works
-
1
Copy the link
Grab the Markdown instruction URL for this feature.
-
2
Give it to your AI
Paste it into Claude Code, Cursor, v0, Lovable — whatever you build with.
-
3
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.