Split View
Let users compare or edit two records side by side without opening another tab.
What it adds
Two independent panes, each holding its own record, its own URL, and its own loading and error state.
What your agent is told to do
5
What your agent is told to do
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Represent both panes in the URL so a split view can be linked, bookmarked, and restored. One pane's record must not be inferable from the other's.
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Give each pane its own fetch, its own loading state, and its own error state. A failure in one pane must leave the other usable.
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Scope actions to the pane they were triggered in. Saving, deleting, or navigating in one pane must never silently swap the other pane's record.
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Below the responsive breakpoint, show one pane at a time with an explicit control to switch, and keep the inactive pane's state rather than discarding it.
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5
Drag handles, minimum and maximum widths, keyboard resizing, and size persistence are owned by Resizable Panels; extend that rather than building a second resize implementation.
Edge cases it handles
6
Edge cases it handles
6- Opening the same record in both panes must either be prevented or kept genuinely in sync — two stale copies of one record is the worst outcome.
- Deleting the record in one pane must leave that pane in a clear removed state, not a blank frame or a redirect that closes the split.
- A restored split view must handle a record that is now deleted or no longer permitted, showing that pane's own error rather than failing the whole view.
- Unsaved edits in a pane must survive the other pane navigating, and must be flagged before the split is closed.
- Keyboard focus must move between panes deliberately, and each pane needs a landmark or label so screen reader users know which is which.
- A global search or command action must have a defined target pane — the focused one — rather than picking one at random.
Definition of done
8
Definition of done
8- Both panes are encoded in the URL and the view restores from it.
- Each pane loads, errors, and empties independently.
- An action in one pane never changes the other pane's record.
- Narrow screens present a single pane with an explicit switch that preserves both panes' state.
- Restoring a split view with a deleted or forbidden record degrades that pane only.
- Resize behaviour is delegated to Resizable Panels, not reimplemented.
- The feature matches the existing design system.
- No existing functionality is broken.
Related features
Beautiful Empty States
Beautiful Empty States
Replace blank screens with useful, contextual empty states.
What it does
Every list, table, and dashboard in your app has a "nothing here yet" state. Most
apps ship a blank rectangle — and it is often the very first thing a new user sees.
An empty state should say what belongs here, why it is empty, and what to do next.
How it works
- 1 Inventory the empty cases first. List every collection view in the app and
- 2 Distinguish the three kinds of empty. They are not the same, and must not
- 3 Build one reusable empty-state component from the existing design system,
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/beautiful-empty-states
Countdown Timer
Countdown Timer
A live countdown to a deadline that ends cleanly instead of running negative.
What it does
A countdown component driven by a server-provided deadline, with a defined finished state.
How it works
- 1 Send the deadline and the server's current time together, compute the offset between server and device once, and count against the corrected value. The device clock cannot be trusted to be right.
- 2 Recompute the remaining time from the corrected clock on every tick rather than decrementing a stored number, so a suspended tab does not resume showing a value minutes behind reality.
- 3 Define the finished state explicitly: what the component shows at zero, whether it reveals something, disables a control, or triggers a refetch. Reuse the app's existing Progress Indicator System styling rather than introducing new type and colour for the digits.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/countdown-timer
Expandable Text
Expandable Text
Shorten long text without making the full content hard to reach.
What it does
Long text clamped to a few lines, with an explicit control to show the rest and collapse it again.
How it works
- 1 Clamp by rendered lines, not by character count. Cutting a string at a fixed length breaks words, mangles markup, and truncates differently at every width.
- 2 Only show the expand control when the text is genuinely clipped. A 'Show more' on a two-line paragraph is noise.
- 3 Use a real button with an accessible label naming what expands, and expose the expanded state. An untagged 'more...' is invisible to a screen reader.
Copy the prompt
No account needed
Add this feature to my app:
https://addthisfeature.com/x/expandable-text
How it works
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1
Copy the link
Grab the Markdown instruction URL for this feature.
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2
Give it to your AI
Paste it into Claude Code, Cursor, v0, Lovable — whatever you build with.
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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.