diff --git a/apps/sim/app/workspace/[workspaceId]/knowledge/[id]/[documentId]/components/chunk-editor/chunk-editor.tsx b/apps/sim/app/workspace/[workspaceId]/knowledge/[id]/[documentId]/components/chunk-editor/chunk-editor.tsx
index bdab7e2a328..74fd800c91f 100644
--- a/apps/sim/app/workspace/[workspaceId]/knowledge/[id]/[documentId]/components/chunk-editor/chunk-editor.tsx
+++ b/apps/sim/app/workspace/[workspaceId]/knowledge/[id]/[documentId]/components/chunk-editor/chunk-editor.tsx
@@ -1,7 +1,7 @@
 'use client'
 
 import React, { useCallback, useEffect, useLayoutEffect, useMemo, useRef, useState } from 'react'
-import { handleKeyboardActivation, Label, Switch } from '@sim/emcn'
+import { handleKeyboardActivation, Label, Switch, toast } from '@sim/emcn'
 import { isApiClientError } from '@/lib/api/client/errors'
 import { requestJson } from '@/lib/api/client/request'
 import { getKnowledgeChunkContract } from '@/lib/api/contracts/knowledge'
@@ -59,6 +59,7 @@ export function ChunkEditor({
 
   const [editedContent, setEditedContent] = useState(isCreateMode ? '' : chunkContent)
   const [savedContent, setSavedContent] = useState(chunkContent)
+  const validationToastIdRef = useRef<string | null>(null)
   const [tokenizerOn, setTokenizerOn] = useState(false)
   const [hoveredTokenIndex, setHoveredTokenIndex] = useState<number | null>(null)
   const savedContentRef = useRef(chunkContent)
@@ -108,8 +109,18 @@ export function ChunkEditor({
   const handleSave = useCallback(async () => {
     const content = editedContentRef.current
     const trimmed = content.trim()
-    if (trimmed.length === 0) throw new Error('Content cannot be empty')
-    if (trimmed.length > 10000) throw new Error('Content exceeds maximum length')
+    /** Toast every failed attempt, replacing the previous validation toast so retries refresh instead of stack. */
+    const failValidation = (message: string): never => {
+      if (validationToastIdRef.current) toast.dismiss(validationToastIdRef.current)
+      validationToastIdRef.current = toast.error(message)
+      throw new Error(message)
+    }
+    if (trimmed.length === 0) failValidation('Content cannot be empty')
+    if (trimmed.length > 10000) failValidation('Content exceeds maximum length (10,000 characters)')
+    if (validationToastIdRef.current) {
+      toast.dismiss(validationToastIdRef.current)
+      validationToastIdRef.current = null
+    }
 
     if (isCreateMode) {
       const created = await createChunk({
diff --git a/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/expanded-cell-popover.tsx b/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/expanded-cell-popover.tsx
index 4e51cef0a82..fc1c7daeb07 100644
--- a/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/expanded-cell-popover.tsx
+++ b/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/expanded-cell-popover.tsx
@@ -197,12 +197,28 @@ function ExpandedCellEditor({
   textareaRef,
 }: ExpandedCellEditorProps) {
   const [draftValue, setDraftValue] = useState(initialValue)
+  const [parseError, setParseError] = useState<string | null>(null)
 
   const handleSave = () => {
     // `displayToStorage` only normalizes dates — it returns null for anything else.
     // Fall back to the raw draft for non-date columns, matching the inline editor.
     const raw = displayToStorage(draftValue) ?? draftValue
-    const cleaned = cleanCellValue(raw, column)
+    let cleaned: unknown
+    try {
+      cleaned = cleanCellValue(raw, column)
+    } catch {
+      setParseError('Invalid JSON')
+      return
+    }
+    /** `cleanCellValue` nulls unparseable dates/numbers instead of throwing — reject rather than silently clear. */
+    if (
+      cleaned === null &&
+      draftValue.trim() !== '' &&
+      (column.type === 'date' || column.type === 'number')
+    ) {
+      setParseError(column.type === 'date' ? 'Invalid date' : 'Invalid number')
+      return
+    }
     onSave(rowId, column.key, cleaned, 'blur')
     onClose()
   }
@@ -219,16 +235,23 @@ function ExpandedCellEditor({
       <textarea
         ref={textareaRef}
         value={draftValue}
-        onChange={(e) => setDraftValue(e.target.value)}
+        onChange={(e) => {
+          setDraftValue(e.target.value)
+          setParseError(null)
+        }}
         onKeyDown={handleTextareaKeyDown}
         className='min-h-0 flex-1 resize-none bg-transparent px-2.5 py-2 font-sans text-[var(--text-primary)] text-small outline-none placeholder:text-[var(--text-muted)]'
         spellCheck={false}
         autoCorrect='off'
       />
       <div className='flex items-center justify-between border-[var(--border)] border-t bg-[var(--surface-2)] px-2 py-1.5'>
-        <span className='text-[var(--text-tertiary)] text-caption'>
-          <kbd className='font-mono'>↵</kbd> save · <kbd className='font-mono'>esc</kbd> cancel
-        </span>
+        {parseError ? (
+          <span className='text-[var(--text-error)] text-caption'>{parseError}</span>
+        ) : (
+          <span className='text-[var(--text-tertiary)] text-caption'>
+            <kbd className='font-mono'>↵</kbd> save · <kbd className='font-mono'>esc</kbd> cancel
+          </span>
+        )}
         <div className='flex items-center gap-1.5'>
           <Button variant='ghost' size='sm' onClick={onClose}>
             Cancel
diff --git a/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/inline-editors.tsx b/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/inline-editors.tsx
index d937a772d33..bbea94ef95d 100644
--- a/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/inline-editors.tsx
+++ b/apps/sim/app/workspace/[workspaceId]/tables/[tableId]/components/table-grid/cells/inline-editors.tsx
@@ -1,7 +1,7 @@
 'use client'
 
 import { useCallback, useEffect, useRef, useState } from 'react'
-import { Calendar, cn, Popover, PopoverAnchor, PopoverContent } from '@sim/emcn'
+import { Calendar, cn, Popover, PopoverAnchor, PopoverContent, toast } from '@sim/emcn'
 import type { ColumnDefinition } from '@/lib/table'
 import type { SaveReason } from '../../../types'
 import {
@@ -44,6 +44,7 @@ function InlineDateEditor({
   const [draft, setDraft] = useState(() =>
     initialCharacter !== undefined ? initialCharacter : storageToDisplay(storedValue)
   )
+  const [invalid, setInvalid] = useState(false)
 
   const pickerValue = displayToStorage(draft) || storedValue || undefined
 
@@ -64,13 +65,24 @@ function InlineDateEditor({
   const doSave = useCallback(
     (reason: SaveReason, storageVal?: string) => {
       if (doneRef.current) return
-      doneRef.current = true
       clearTimeout(blurTimeoutRef.current)
       const raw = storageVal ?? displayToStorage(draft) ?? draft
-      const val = raw && !Number.isNaN(Date.parse(raw)) ? raw : null
-      onSave(val, reason)
+      if (raw && Number.isNaN(Date.parse(raw))) {
+        if (reason === 'blur') {
+          if (!invalid) toast.error('Invalid date')
+          doneRef.current = true
+          onCancel()
+        } else {
+          toast.error('Invalid date')
+          setInvalid(true)
+          inputRef.current?.focus()
+        }
+        return
+      }
+      doneRef.current = true
+      onSave(raw || null, reason)
     },
-    [draft, onSave]
+    [draft, invalid, onSave, onCancel]
   )
 
   const handleKeyDown = useCallback(
@@ -116,12 +128,16 @@ function InlineDateEditor({
         ref={inputRef}
         type='text'
         value={draft}
-        onChange={(e) => setDraft(e.target.value)}
+        onChange={(e) => {
+          setDraft(e.target.value)
+          setInvalid(false)
+        }}
         onKeyDown={handleKeyDown}
         onBlur={handleBlur}
         placeholder='mm/dd/yyyy'
         className={cn(
-          'w-full min-w-0 select-text border-none bg-transparent p-0 text-[var(--text-primary)] text-small outline-none'
+          'w-full min-w-0 select-text border-none bg-transparent p-0 text-[var(--text-primary)] text-small outline-none',
+          invalid && 'text-[var(--text-error)]'
         )}
       />
       <Popover open onOpenChange={handlePickerOpenChange}>
@@ -146,6 +162,7 @@ function InlineTextEditor({
   const [draft, setDraft] = useState(() =>
     initialCharacter !== undefined ? initialCharacter : formatValueForInput(value, column.type)
   )
+  const [invalid, setInvalid] = useState(false)
   const doneRef = useRef(false)
 
   useEffect(() => {
@@ -161,14 +178,33 @@ function InlineTextEditor({
     }
   }, [])
 
+  const rejectDraft = (message: string, reason: SaveReason) => {
+    if (reason === 'blur') {
+      if (!invalid) toast.error(message)
+      doneRef.current = true
+      onCancel()
+    } else {
+      toast.error(message)
+      setInvalid(true)
+      inputRef.current?.focus()
+    }
+  }
+
   const doSave = (reason: SaveReason) => {
     if (doneRef.current) return
-    doneRef.current = true
+    let cleaned: unknown
     try {
-      onSave(cleanCellValue(draft, column), reason)
+      cleaned = cleanCellValue(draft, column)
     } catch {
-      onCancel()
+      rejectDraft('Invalid JSON', reason)
+      return
+    }
+    if (column.type === 'number' && cleaned === null && draft.trim() !== '') {
+      rejectDraft('Invalid number', reason)
+      return
     }
+    doneRef.current = true
+    onSave(cleaned, reason)
   }
 
   const handleKeyDown = (e: React.KeyboardEvent) => {
@@ -193,11 +229,17 @@ function InlineTextEditor({
       type='text'
       inputMode={isNumber ? 'decimal' : undefined}
       value={draft ?? ''}
-      onChange={(e) => setDraft(e.target.value)}
+      onChange={(e) => {
+        setDraft(e.target.value)
+        setInvalid(false)
+      }}
       onKeyDown={handleKeyDown}
       onWheel={handleEditorWheel}
       onBlur={() => doSave('blur')}
-      className='w-full min-w-0 select-text border-none bg-transparent p-0 text-[var(--text-primary)] text-small outline-none'
+      className={cn(
+        'w-full min-w-0 select-text border-none bg-transparent p-0 text-[var(--text-primary)] text-small outline-none',
+        invalid && 'text-[var(--text-error)]'
+      )}
     />
   )
 }
diff --git a/apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/deploy/components/deploy-modal/components/general/components/version-description-modal.tsx b/apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/deploy/components/deploy-modal/components/general/components/version-description-modal.tsx
index 245ad88ede4..0ad21cd9b2e 100644
--- a/apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/deploy/components/deploy-modal/components/general/components/version-description-modal.tsx
+++ b/apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/deploy/components/deploy-modal/components/general/components/version-description-modal.tsx
@@ -30,7 +30,7 @@ const RichMarkdownField = dynamic(
   }
 )
 
-/** A high cap that only guards against abuse — no visible counter; normal descriptions never reach it. */
+/** A high cap that only guards against abuse — a counter message appears only when exceeded. */
 const MAX_DESCRIPTION_LENGTH = 50_000
 
 interface VersionDescriptionModalProps {
@@ -136,6 +136,11 @@ export function VersionDescriptionModal({
                 <span className='font-medium text-[var(--text-primary)]'>{versionName}</span>
               </span>
             }
+            error={
+              isTooLong
+                ? `Description exceeds the ${MAX_DESCRIPTION_LENGTH.toLocaleString()}-character limit (currently ${description.length.toLocaleString()})`
+                : undefined
+            }
           >
             <RichMarkdownField
               value={description}
@@ -145,7 +150,7 @@ export function VersionDescriptionModal({
               maxHeight={420}
               disabled={isGenerating}
               isStreaming={isGenerating}
-              error={description.length > MAX_DESCRIPTION_LENGTH}
+              error={isTooLong}
               workspaceId={workspaceId}
               disableTagging
             />
diff --git a/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/components/workspace-header/components/create-workspace-modal/create-workspace-modal.tsx b/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/components/workspace-header/components/create-workspace-modal/create-workspace-modal.tsx
index 5ef6dbb3eeb..9190eefa696 100644
--- a/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/components/workspace-header/components/create-workspace-modal/create-workspace-modal.tsx
+++ b/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/components/workspace-header/components/create-workspace-modal/create-workspace-modal.tsx
@@ -1,6 +1,6 @@
 'use client'
 
-import { useEffect, useState } from 'react'
+import { useState } from 'react'
 import {
   ChipModal,
   ChipModalBody,
@@ -9,6 +9,7 @@ import {
   ChipModalFooter,
   ChipModalHeader,
 } from '@sim/emcn'
+import { getErrorMessage } from '@sim/utils/errors'
 
 interface CreateWorkspaceModalProps {
   open: boolean
@@ -27,17 +28,25 @@ export function CreateWorkspaceModal({
   isCreating,
 }: CreateWorkspaceModalProps) {
   const [name, setName] = useState('')
+  const [error, setError] = useState<string | null>(null)
 
-  useEffect(() => {
+  const [prevOpen, setPrevOpen] = useState(open)
+  if (prevOpen !== open) {
+    setPrevOpen(open)
     if (open) {
       setName('')
+      setError(null)
     }
-  }, [open])
+  }
 
   const handleSubmit = async () => {
     const trimmed = name.trim()
     if (!trimmed || isCreating) return
-    await onConfirm(trimmed)
+    try {
+      await onConfirm(trimmed)
+    } catch (err) {
+      setError(getErrorMessage(err, 'Failed to create workspace'))
+    }
   }
 
   const handleKeyDown = (e: React.KeyboardEvent) => {
@@ -47,6 +56,11 @@ export function CreateWorkspaceModal({
     }
   }
 
+  const handleNameChange = (value: string) => {
+    setName(value)
+    setError(null)
+  }
+
   return (
     <ChipModal open={open} onOpenChange={onOpenChange} srTitle='Create workspace'>
       <ChipModalHeader onClose={() => onOpenChange(false)}>Create workspace</ChipModalHeader>
@@ -55,14 +69,14 @@ export function CreateWorkspaceModal({
           type='input'
           title='Name'
           value={name}
-          onChange={setName}
+          onChange={handleNameChange}
           placeholder='Workspace name'
           maxLength={100}
           autoComplete='off'
           disabled={isCreating}
           required
         />
-        <ChipModalError>{undefined}</ChipModalError>
+        <ChipModalError>{error ?? undefined}</ChipModalError>
       </ChipModalBody>
       <ChipModalFooter
         onCancel={() => onOpenChange(false)}
diff --git a/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/hooks/use-workspace-management.ts b/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/hooks/use-workspace-management.ts
index 69cb48f4b23..c3d6aeba3e9 100644
--- a/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/hooks/use-workspace-management.ts
+++ b/apps/sim/app/workspace/[workspaceId]/w/components/sidebar/hooks/use-workspace-management.ts
@@ -176,6 +176,7 @@ export function useWorkspaceManagement({
         await switchWorkspace(newWorkspace)
       } catch (error) {
         logger.error('Error creating workspace:', error)
+        throw error
       }
     },
     // eslint-disable-next-line react-hooks/exhaustive-deps