diff --git a/api/core/tools/tool_manager.py b/api/core/tools/tool_manager.py
index 7472f4f60..2089313b0 100644
--- a/api/core/tools/tool_manager.py
+++ b/api/core/tools/tool_manager.py
@@ -959,7 +959,7 @@ class ToolManager:
         elif provider_type == ToolProviderType.WORKFLOW:
             return cls.generate_workflow_tool_icon_url(tenant_id, provider_id)
         elif provider_type == ToolProviderType.PLUGIN:
-            provider = ToolManager.get_builtin_provider(provider_id, tenant_id)
+            provider = ToolManager.get_plugin_provider(provider_id, tenant_id)
             if isinstance(provider, PluginToolProviderController):
                 try:
                     return cls.generate_plugin_tool_icon_url(tenant_id, provider.entity.identity.icon)
diff --git a/api/core/tools/workflow_as_tool/provider.py b/api/core/tools/workflow_as_tool/provider.py
index 83f5f558d..18e6993b3 100644
--- a/api/core/tools/workflow_as_tool/provider.py
+++ b/api/core/tools/workflow_as_tool/provider.py
@@ -203,9 +203,6 @@ class WorkflowToolProviderController(ToolProviderController):
             raise ValueError("app not found")
 
         app = db_providers.app
-        if not app:
-            raise ValueError("can not read app of workflow")
-
         self.tools = [self._get_db_provider_tool(db_providers, app)]
 
         return self.tools