Multiple bugs in attachments.tsx and prompt-input.tsx

[oleics]

Hi,

after a fresh install of shadcn (base) and a subsequent shadcn add ... of some ai-elements components, I've found some bugs:

attachments.tsx

• the AttachmentHoverCard component is broken, openDelay and closeDelay are not defined, and closeDelay does not exist on AttachmentHoverCard

prompt-input.tsx

• the PromptInputActionAddAttachments component is broken as DropdownMenuItem does not have a onSelect property
• same is true for the PromptInputActionAddScreenshot, additionally onSelect has wrong typings
• PromptInputHoverCard is broken in the same way as AttachmentHoverCard from attachments.tsx

conversation.tsx, model-selector.tsx and message.tsx seem to be fine, though.

[TrentM1997]

I took a look into this, and from what I gather I think this may be specific to a shadcn project created with Base UI. The delay defaults in the props for the AttachmentHoverCard component fall back to 0 when undefined so they shouldn't stay undefined at runtime.

It looks like AI Elements expects Radix specific props like openDelay and closeDelay, while the equivalent Base UI components may expose a different API.

Was the project initialized with Base UI? If so my suspicion would be that this is a Base UI compatibility issue.

[hamchowderr]

Confirming this on shadcn CLI 4.16.0 / Next 16.2.6 (2026-08-02), with the exact tsc output and two files this issue doesn't yet cover.

Repro: shadcn init --base base --preset nova (style base-nova), then add the components. 12 errors across 4 files:

7  components/ai-elements/prompt-input.tsx
3  components/ai-elements/attachments.tsx
1  components/ai-elements/inline-citation.tsx
1  components/ai-elements/plan.tsx

openDelay / closeDelay — 6 errors. As reported, plus inline-citation.tsx, which isn't mentioned above:

attachments.tsx(375,3): error TS2339: Property 'openDelay' does not exist on type 'Props<unknown>'.
attachments.tsx(376,3): error TS2339: Property 'closeDelay' does not exist on type 'Props<unknown>'.
attachments.tsx(379,14): error TS2322: Type '{ ...; openDelay: any; }' is not assignable to type 'IntrinsicAttributes & Props<unknown>'.
inline-citation.tsx(53,14): error TS2322: Type '{ ...; openDelay: number; }' is not assignable to type 'IntrinsicAttributes & Props<unknown>'.
prompt-input.tsx(1317,3): error TS2339: Property 'openDelay' does not exist on type 'Props<unknown>'.
prompt-input.tsx(1318,3): error TS2339: Property 'closeDelay' does not exist on type 'Props<unknown>'.
prompt-input.tsx(1321,14): error TS2322: Type '{ ...; openDelay: any; }' is not assignable to type 'IntrinsicAttributes & Props<unknown>'.

Handler event signatures — 4 errors, all prompt-input.tsx. Base UI wraps events in BaseUIEvent<…>:

prompt-input.tsx(432,34): error TS2322: Type '(e: Event) => void' is not assignable to type '(event: BaseUIEvent<SyntheticEvent<HTMLDivElement, Event>>) => void'.
prompt-input.tsx(453,18): error TS2345: Argument of type 'Event' is not assignable to parameter of type 'BaseUIEvent<SyntheticEvent<HTMLDivElement, Event>>'.
prompt-input.tsx(477,34): error TS2322: Type '(event: Event) => Promise<void>' is not assignable to type '(event: BaseUIEvent<SyntheticEvent<HTMLDivElement, Event>>) => void'.
prompt-input.tsx(1241,17): error TS2345: Argument of type 'MouseEvent<HTMLButtonElement, MouseEvent>' is not assignable to parameter of type 'BaseUIEvent<MouseEvent<HTMLButtonElement, MouseEvent>>'.

One more file not listed here — plan.tsx:

plan.tsx(131,32): error TS2322: Type '{ nativeButton?: boolean | undefined; ...; variant: "ghost"; }' is not assignable to type 'ButtonProps'.

For reference, conversation.tsx, model-selector.tsx and message.tsx are clean here too, matching the original report.

The delay props are the easy half — the same pattern fixes all 6. Sending a PR for that shortly; the BaseUIEvent ones are a real typing change and I've left them alone.