improvement(emcn): show per-chip error tooltips on invalid email chips

apps/sim/app/playground/page.tsx

@@ -152,7 +152,7 @@ export default function PlaygroundPage() {
   const [dateRangeEnd, setDateRangeEnd] = useState('')
   const [tagItems, setTagItems] = useState<TagItem[]>([
     { value: 'user@example.com', isValid: true },
-    { value: 'invalid-email', isValid: false },
+    { value: 'invalid-email', isValid: false, error: 'Invalid email format' },
   ])
 
   const toggleDarkMode = () => {

apps/sim/app/workspace/[workspaceId]/settings/components/credential-sets/credential-sets.tsx

@@ -134,7 +134,14 @@ export function CredentialSets() {
         return false
       }
 
-      setEmailItems((prev) => [...prev, { value: normalized, isValid }])
+      setEmailItems((prev) => [
+        ...prev,
+        {
+          value: normalized,
+          isValid,
+          error: isValid ? undefined : (validation.reason ?? 'Invalid email format'),
+        },
+      ])
 
       if (isValid) {
         setEmailError(null)

apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/deploy/components/deploy-modal/components/chat/chat.tsx

@@ -655,7 +655,10 @@ function AuthSelector({
       setEmailError('')
       onEmailsChange([...emails, normalized])
     } else {
-      setInvalidEmailItems((prev) => [...prev, { value: normalized, isValid }])
+      setInvalidEmailItems((prev) => [
+        ...prev,
+        { value: normalized, isValid, error: validation.reason ?? 'Invalid email format' },
+      ])
     }
 
     return isValid

apps/sim/components/emcn/components/chip-modal/chip-modal.tsx

@@ -388,12 +388,14 @@ export interface ChipModalEmailsFieldProps extends ChipModalFieldBaseProps {
   /**
    * Optional domain-level validator. Runs AFTER the field's internal format
    * check passes. Return an error message to reject the email (added as an
-   * invalid chip and surfaced in the inline banner); return `null` to accept.
+   * invalid chip whose reason shows in a tooltip on hover); return `null`
+   * to accept.
    */
   validate?: (email: string) => string | null
   /**
-   * External error (e.g. server-side submit failure). Takes precedence over
-   * the field's internal validation banner while present.
+   * External error (e.g. server-side submit failure), rendered in the inline
+   * banner below the field. Per-email rejection reasons are shown on the
+   * invalid chips themselves, not here.
    */
   error?: React.ReactNode
   /** Auto-focus the input when the field mounts. */
@@ -561,8 +563,11 @@ function derivePlaceholderWithTags(placeholder: string): string {
 
 /**
  * Internal renderer for {@link ChipModalField} `type='emails'`. Owns the
- * chip lifecycle (valid + invalid items, dedupe, inline error banner) and
- * lifts only the valid email list up to the consumer via `onChange`.
+ * chip lifecycle (valid + invalid items, dedupe, per-chip error tooltips)
+ * and lifts only the valid email list up to the consumer via `onChange`.
+ * Each rejected entry carries its rejection reason on the chip itself,
+ * surfaced as a tooltip; the inline banner is reserved for the consumer's
+ * `error` (e.g. server-side submit failures).
  */
 function ChipModalEmailsControl({
   value,
@@ -576,7 +581,6 @@ function ChipModalEmailsControl({
   errorId,
 }: ChipModalEmailsFieldProps & { id: string; errorId: string }) {
   const [items, setItems] = React.useState<TagItem[]>([])
-  const [internalError, setInternalError] = React.useState<string | null>(null)
 
   /**
    * Reconcile internal `items` with the consumer's `value` when the latter
@@ -600,23 +604,24 @@ function ChipModalEmailsControl({
       if (!email) return false
       if (items.some((item) => item.value === email)) return false
 
-      if (!quickValidateEmail(email).isValid) {
-        setItems((prev) => [...prev, { value: email, isValid: false }])
-        setInternalError(null)
+      const formatCheck = quickValidateEmail(email)
+      if (!formatCheck.isValid) {
+        setItems((prev) => [
+          ...prev,
+          { value: email, isValid: false, error: formatCheck.reason ?? 'Invalid email format' },
+        ])
         return false
       }
 
       const reason = validate?.(email)
       if (reason) {
-        setItems((prev) => [...prev, { value: email, isValid: false }])
-        setInternalError(reason)
+        setItems((prev) => [...prev, { value: email, isValid: false, error: reason }])
         return false
       }
 
       const next = [...items, { value: email, isValid: true }]
       setItems(next)
       onChange(next.filter((item) => item.isValid).map((item) => item.value))
-      setInternalError(null)
       return true
     },
     [items, validate, onChange]
@@ -630,34 +635,26 @@ function ChipModalEmailsControl({
       if (wasValid) {
         onChange(next.filter((item) => item.isValid).map((item) => item.value))
       }
-      setInternalError(null)
     },
     [items, onChange]
   )
 
-  const handleInputChange = React.useCallback(() => {
-    setInternalError(null)
-  }, [])
-
-  const banner = error ?? internalError
-
   return (
     <>
       <TagInput
         variant='block'
         items={items}
         onAdd={handleAdd}
         onRemove={handleRemove}
-        onInputChange={handleInputChange}
         placeholder={placeholder}
         placeholderWithTags={derivePlaceholderWithTags(placeholder)}
         disabled={disabled}
         autoFocus={autoFocus}
         id={id}
       />
-      {banner && (
+      {error && (
         <p id={errorId} role='alert' className={CHIP_MODAL_FIELD_ERROR_CLASS}>
-          {banner}
+          {error}
         </p>
       )}
     </>

apps/sim/components/emcn/components/tag-input/tag-input.tsx

@@ -81,6 +81,11 @@ const tagInputVariants = cva(
 export interface TagItem {
   value: string
   isValid: boolean
+  /**
+   * Why the item is invalid. Shown in a tooltip on the invalid chip (and as
+   * screen-reader-only text inside it). Ignored when `isValid` is true.
+   */
+  error?: string
 }
 
 /**
@@ -162,7 +167,9 @@ const TagInputTag = React.memo(function TagInputTag({
     onRemove(item.value, index, item.isValid)
   }, [item.value, item.isValid, index, onRemove])
 
-  return (
+  const showError = !item.isValid && !!item.error
+
+  const tag = (
     <ChipTag
       variant='invite'
       invalid={!item.isValid}
@@ -174,9 +181,19 @@ const TagInputTag = React.memo(function TagInputTag({
       <span className='min-w-0 flex-1 translate-y-[0.5px] truncate font-medium font-sans text-sm leading-5'>
         {item.value}
       </span>
+      {showError && <span className='sr-only'>{item.error}</span>}
       {suffix}
     </ChipTag>
   )
+
+  if (!showError) return tag
+
+  return (
+    <Tooltip.Root>
+      <Tooltip.Trigger asChild>{tag}</Tooltip.Trigger>
+      <Tooltip.Content>{item.error}</Tooltip.Content>
+    </Tooltip.Root>
+  )
 })
 
 /**