Expose agent node usage (#24355)

web/app/components/workflow/constants.ts

@@ -467,6 +467,13 @@ export const SUPPORT_OUTPUT_VARS_NODE = [
   BlockEnum.Agent,
 ]
 
+export const AGENT_OUTPUT_STRUCT: Var[] = [
+  {
+    variable: 'usage',
+    type: VarType.object,
+  },
+]
+
 export const LLM_OUTPUT_STRUCT: Var[] = [
   {
     variable: 'text',

web/app/components/workflow/nodes/_base/components/variable/utils.ts

@@ -24,6 +24,7 @@ import type { VariableAssignerNodeType } from '@/app/components/workflow/nodes/v
 import type { Field as StructField } from '@/app/components/workflow/nodes/llm/types'
 
 import {
+  AGENT_OUTPUT_STRUCT,
   HTTP_REQUEST_OUTPUT_STRUCT,
   KNOWLEDGE_RETRIEVAL_OUTPUT_STRUCT,
   LLM_OUTPUT_STRUCT,
@@ -498,6 +499,7 @@ const formatItem = (
       res.vars = [
         ...outputs,
         ...TOOL_OUTPUT_STRUCT,
+        ...AGENT_OUTPUT_STRUCT,
       ]
       break
     }

web/app/components/workflow/nodes/agent/panel.tsx

@@ -100,6 +100,11 @@ const AgentPanel: FC<NodePanelProps<AgentNodeType>> = (props) => {
           type='String'
           description={t(`${i18nPrefix}.outputVars.text`)}
         />
+        <VarItem
+          name='usage'
+          type='object'
+          description={t(`${i18nPrefix}.outputVars.usage`)}
+        />
         <VarItem
           name='files'
           type='Array[File]'