fix(workflow): resolve MCP tool names from live server data in canvas summaries

resolveToolsLabel preferred the stored title for mcp entries, so canvas
and preview summaries could show a state-edited name while the config
panel showed the live MCP tool name. Accept an optional mcpTools list
(matched by toolId, same as the panel) and pass the already-fetched MCP
tool data from workflow-block; the stored title remains the fallback
while server data is unavailable.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

Author: j15z

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

@@ -331,9 +331,13 @@ const SubBlockRow = memo(function SubBlockRow({
 
   /** Hydrates tool references to display names. */
   const { data: customTools = [] } = useCustomTools(workspaceId || '')
+  const mcpToolSummaries = useMemo(
+    () => mcpToolsData.map((t) => ({ id: createMcpToolId(t.serverId, t.name), name: t.name })),
+    [mcpToolsData]
+  )
   const toolsDisplayValue = useMemo(
-    () => resolveToolsLabel(subBlock, rawValue, customTools),
-    [subBlock, rawValue, customTools]
+    () => resolveToolsLabel(subBlock, rawValue, customTools, mcpToolSummaries),
+    [subBlock, rawValue, customTools, mcpToolSummaries]
   )
 
   const filterDisplayValue = useMemo(

apps/sim/lib/workflows/subblocks/display.test.ts

@@ -135,6 +135,20 @@ describe('resolveToolsLabel', () => {
     expect(resolveToolsLabel(toolInput, [{ type: 'workflow_input' }], [])).toBe('Workflow')
   })
 
+  it('prefers the live MCP tool name over the stored title', () => {
+    expect(
+      resolveToolsLabel(
+        toolInput,
+        [{ type: 'mcp', toolId: 'mcp-1', title: 'Renamed By Copilot' }],
+        [],
+        [{ id: 'mcp-1', name: 'Live MCP Name' }]
+      )
+    ).toBe('Live MCP Name')
+    expect(
+      resolveToolsLabel(toolInput, [{ type: 'mcp', toolId: 'mcp-1', title: 'Snapshot' }], [], [])
+    ).toBe('Snapshot')
+  })
+
   it('prefers the custom tool record over the stored title', () => {
     expect(
       resolveToolsLabel(

apps/sim/lib/workflows/subblocks/display.ts

@@ -428,15 +428,17 @@ export function resolveVariablesLabel(
 
 /**
  * Resolves a tool-input value to a tool-name summary. Names come from static
- * sources first (block registry, custom-tool records) so that edits to the
- * stored entry's `title` cannot change what the UI shows; the stored title
- * and inline schema names are only fallbacks for shapes with no canonical
- * source (MCP snapshots, legacy entries).
+ * sources first (block registry, custom-tool records, live MCP tools) so that
+ * edits to the stored entry's `title` cannot change what the UI shows; the
+ * stored title and inline schema names are only fallbacks for shapes with no
+ * canonical source (MCP entries while server data is unavailable, legacy
+ * entries).
  */
 export function resolveToolsLabel(
   subBlock: SubBlockConfig | undefined,
   rawValue: unknown,
-  customTools: Array<{ id: string; title?: string; schema?: { function?: { name?: string } } }>
+  customTools: Array<{ id: string; title?: string; schema?: { function?: { name?: string } } }>,
+  mcpTools: Array<{ id: string; name: string }> = []
 ): string | null {
   if (subBlock?.type !== 'tool-input') return null
   if (!Array.isArray(rawValue) || rawValue.length === 0) return null
@@ -466,6 +468,11 @@ export function resolveToolsLabel(
         if (customTool?.schema?.function?.name) return customTool.schema.function.name
       }
 
+      if (t.type === 'mcp' && typeof t.toolId === 'string') {
+        const mcpTool = mcpTools.find((candidate) => candidate.id === t.toolId)
+        if (mcpTool?.name) return mcpTool.name
+      }
+
       if (typeof t.title === 'string' && t.title) return t.title
 
       const schema = t.schema as { function?: { name?: string } } | undefined