Fix start block numbering (#1909)

apps/sim/app/workspace/[workspaceId]/w/[workflowId]/components/workflow-block/components/action-bar/action-bar.tsx

@@ -55,6 +55,8 @@ export const ActionBar = memo(
     const userPermissions = useUserPermissionsContext()
 
     const isStarterBlock = blockType === 'starter'
+    // Check for start_trigger (unified start block) - prevent duplication but allow deletion
+    const isStartBlock = blockType === 'starter' || blockType === 'start_trigger'
 
     /**
      * Get appropriate tooltip message based on disabled state
@@ -103,7 +105,7 @@ export const ActionBar = memo(
           </Tooltip.Content>
         </Tooltip.Root>
 
-        {!isStarterBlock && (
+        {!isStartBlock && (
           <Tooltip.Root>
             <Tooltip.Trigger asChild>
               <Button
@@ -124,7 +126,7 @@ export const ActionBar = memo(
           </Tooltip.Root>
         )}
 
-        {!isStarterBlock && parentId && (parentType === 'loop' || parentType === 'parallel') && (
+        {!isStartBlock && parentId && (parentType === 'loop' || parentType === 'parallel') && (
           <Tooltip.Root>
             <Tooltip.Trigger asChild>
               <Button
@@ -174,26 +176,24 @@ export const ActionBar = memo(
           </Tooltip.Content>
         </Tooltip.Root>
 
-        {!isStarterBlock && (
-          <Tooltip.Root>
-            <Tooltip.Trigger asChild>
-              <Button
-                variant='ghost'
-                onClick={(e) => {
-                  e.stopPropagation()
-                  if (!disabled) {
-                    collaborativeRemoveBlock(blockId)
-                  }
-                }}
-                className='h-[30px] w-[30px] rounded-[8px] bg-[#363636] p-0 text-[#868686] hover:bg-[#33B4FF] hover:text-[#1B1B1B] dark:text-[#868686] dark:hover:bg-[#33B4FF] dark:hover:text-[#1B1B1B]'
-                disabled={disabled}
-              >
-                <Trash2 className='h-[14px] w-[14px]' />
-              </Button>
-            </Tooltip.Trigger>
-            <Tooltip.Content side='right'>{getTooltipMessage('Delete Block')}</Tooltip.Content>
-          </Tooltip.Root>
-        )}
+        <Tooltip.Root>
+          <Tooltip.Trigger asChild>
+            <Button
+              variant='ghost'
+              onClick={(e) => {
+                e.stopPropagation()
+                if (!disabled) {
+                  collaborativeRemoveBlock(blockId)
+                }
+              }}
+              className='h-[30px] w-[30px] rounded-[8px] bg-[#363636] p-0 text-[#868686] hover:bg-[#33B4FF] hover:text-[#1B1B1B] dark:text-[#868686] dark:hover:bg-[#33B4FF] dark:hover:text-[#1B1B1B]'
+              disabled={disabled}
+            >
+              <Trash2 className='h-[14px] w-[14px]' />
+            </Button>
+          </Tooltip.Trigger>
+          <Tooltip.Content side='right'>{getTooltipMessage('Delete Block')}</Tooltip.Content>
+        </Tooltip.Root>
       </div>
     )
   },

apps/sim/hooks/use-collaborative-workflow.ts

@@ -1193,6 +1193,15 @@ export function useCollaborativeWorkflow() {
       const sourceBlock = workflowStore.blocks[sourceId]
       if (!sourceBlock) return
 
+      // Prevent duplication of start blocks (both legacy starter and unified start_trigger)
+      if (sourceBlock.type === 'starter' || sourceBlock.type === 'start_trigger') {
+        logger.warn('Cannot duplicate start block - only one start block allowed per workflow', {
+          blockId: sourceId,
+          blockType: sourceBlock.type,
+        })
+        return
+      }
+
       // Generate new ID and calculate position
       const newId = crypto.randomUUID()
       const offsetPosition = {

apps/sim/lib/workflows/triggers.ts

@@ -59,6 +59,7 @@ const START_CONFLICT_TYPES: TriggerType[] = [
   TRIGGER_TYPES.INPUT,
   TRIGGER_TYPES.MANUAL,
   TRIGGER_TYPES.CHAT,
+  TRIGGER_TYPES.STARTER, // Legacy starter also conflicts with start_trigger
 ]
 
 type BlockWithType = { type: string; subBlocks?: Record<string, unknown> | undefined }

apps/sim/stores/workflows/utils.ts

@@ -18,6 +18,13 @@ export function normalizeBlockName(name: string): string {
  * @returns A unique block name with an appropriate number suffix
  */
 export function getUniqueBlockName(baseName: string, existingBlocks: Record<string, any>): string {
+  // Special case: Start blocks should always be named "Start" without numbers
+  // This applies to both "Start" and "Starter" base names
+  const normalizedBaseName = normalizeBlockName(baseName)
+  if (normalizedBaseName === 'start' || normalizedBaseName === 'starter') {
+    return 'Start'
+  }
+
   const baseNameMatch = baseName.match(/^(.*?)(\s+\d+)?$/)
   const namePrefix = baseNameMatch ? baseNameMatch[1].trim() : baseName