diff --git a/api/core/workflow/nodes/agent/agent_node.py b/api/core/workflow/nodes/agent/agent_node.py
index 68a24e86b1..d8b0ea3afd 100644
--- a/api/core/workflow/nodes/agent/agent_node.py
+++ b/api/core/workflow/nodes/agent/agent_node.py
@@ -10,6 +10,7 @@ from graphon.node_events import NodeEventBase, NodeRunResult, StreamCompletedEve
 from graphon.nodes.base.node import Node
 from graphon.nodes.base.variable_template_parser import VariableTemplateParser
 
+from .clarification_helper import should_enable_clarification
 from .entities import AgentNodeData
 from .exceptions import (
     AgentInvocationError,
@@ -154,6 +155,11 @@ class AgentNode(Node[AgentNodeData]):
                 node_id=self._node_id,
                 node_execution_id=self.id,
             )
+            # Extensibility hook for human clarification (HITL support)
+            # Currently a no-op, but allows future HITL implementation
+            if should_enable_clarification(self.node_data):
+                # Placeholder for future clarification logic
+                pass
         except PluginDaemonClientSideError as e:
             transform_error = AgentMessageTransformError(
                 f"Failed to transform agent message: {str(e)}", original_error=e
diff --git a/api/core/workflow/nodes/agent/clarification_helper.py b/api/core/workflow/nodes/agent/clarification_helper.py
new file mode 100644
index 0000000000..0debf19f47
--- /dev/null
+++ b/api/core/workflow/nodes/agent/clarification_helper.py
@@ -0,0 +1,51 @@
+"""
+Clarification helper for agent node human-in-the-loop support.
+
+This module provides extensibility hooks for future HITL (Human-In-The-Loop) features.
+Currently, it serves as a placeholder for clarification request extraction and handling.
+"""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING, Any
+
+if TYPE_CHECKING:
+    from .entities import AgentNodeData
+
+
+def should_enable_clarification(node_data: AgentNodeData) -> bool:
+    """
+    Check if human clarification is enabled for this agent node.
+
+    Args:
+        node_data: The agent node data configuration.
+
+    Returns:
+        True if human clarification is enabled, False otherwise.
+    """
+    return node_data.enable_human_clarification
+
+
+def extract_clarification_request(
+    _agent_output: dict[str, Any],
+    enable_clarification: bool,
+) -> dict[str, Any] | None:
+    """
+    Extract clarification request from agent output if enabled.
+
+    This is a placeholder for future HITL implementation.
+    Currently returns None as clarification is not yet implemented.
+
+    Args:
+        _agent_output: The output from agent execution. Currently unused, reserved for future HITL expansion.
+        enable_clarification: Whether clarification is enabled.
+
+    Returns:
+        Clarification request dict if found and enabled, None otherwise.
+    """
+    if not enable_clarification:
+        return None
+
+    # Placeholder for future clarification extraction logic
+    # This will be extended when HITL feature is fully implemented
+    return None
diff --git a/api/core/workflow/nodes/agent/entities.py b/api/core/workflow/nodes/agent/entities.py
index 51452c29a3..59be05f121 100644
--- a/api/core/workflow/nodes/agent/entities.py
+++ b/api/core/workflow/nodes/agent/entities.py
@@ -19,6 +19,8 @@ class AgentNodeData(BaseNodeData):
     # If this value is None, it indicates this is a previous version
     # and requires using the legacy parameter parsing rules.
     tool_node_version: str | None = None
+    # Enable human clarification for agent reasoning
+    enable_human_clarification: bool = False
 
     class AgentInput(BaseModel):
         value: Union[list[str], list[ToolSelector], Any]
diff --git a/api/tests/unit_tests/core/workflow/nodes/agent/test_clarification_helper.py b/api/tests/unit_tests/core/workflow/nodes/agent/test_clarification_helper.py
new file mode 100644
index 0000000000..d15e173ad8
--- /dev/null
+++ b/api/tests/unit_tests/core/workflow/nodes/agent/test_clarification_helper.py
@@ -0,0 +1,80 @@
+"""
+Tests for agent node clarification helper and configuration.
+"""
+
+import pytest
+
+from core.workflow.nodes.agent.clarification_helper import (
+    extract_clarification_request,
+    should_enable_clarification,
+)
+from core.workflow.nodes.agent.entities import AgentNodeData
+
+
+@pytest.fixture
+def base_node_data_args() -> dict:
+    """Fixture providing base arguments for AgentNodeData construction."""
+    return {
+        "id": "test_node",
+        "type": "agent",
+        "agent_strategy_provider_name": "test_provider",
+        "agent_strategy_name": "test_strategy",
+        "agent_strategy_label": "Test Strategy",
+        "agent_parameters": {},
+    }
+
+
+class TestClarificationHelper:
+    """Test suite for clarification helper functions."""
+
+    def test_should_enable_clarification_when_enabled(self, base_node_data_args):
+        """Test that should_enable_clarification returns True when enabled."""
+        node_data = AgentNodeData(
+            **base_node_data_args,
+            enable_human_clarification=True,
+        )
+        assert should_enable_clarification(node_data) is True
+
+    def test_should_enable_clarification_when_disabled(self, base_node_data_args):
+        """Test that should_enable_clarification returns False when disabled."""
+        node_data = AgentNodeData(
+            **base_node_data_args,
+            enable_human_clarification=False,
+        )
+        assert should_enable_clarification(node_data) is False
+
+    def test_should_enable_clarification_default_false(self, base_node_data_args):
+        """Test that clarification is disabled by default."""
+        node_data = AgentNodeData(**base_node_data_args)
+        assert should_enable_clarification(node_data) is False
+
+    def test_extract_clarification_request_when_disabled(self):
+        """Test that extract_clarification_request returns None when disabled."""
+        result = extract_clarification_request(
+            _agent_output={"text": "test output"},
+            enable_clarification=False,
+        )
+        assert result is None
+
+    def test_extract_clarification_request_when_enabled(self):
+        """Test that extract_clarification_request returns None when enabled (placeholder)."""
+        # Currently returns None as placeholder for future implementation
+        result = extract_clarification_request(
+            _agent_output={"text": "test output"},
+            enable_clarification=True,
+        )
+        assert result is None
+
+    def test_agent_node_data_with_clarification_field(self, base_node_data_args):
+        """Test that AgentNodeData properly stores enable_human_clarification."""
+        node_data = AgentNodeData(
+            **base_node_data_args,
+            enable_human_clarification=True,
+        )
+        assert node_data.enable_human_clarification is True
+
+        node_data_disabled = AgentNodeData(
+            **base_node_data_args,
+            enable_human_clarification=False,
+        )
+        assert node_data_disabled.enable_human_clarification is False
diff --git a/web/app/components/workflow/nodes/agent/panel.spec.tsx b/web/app/components/workflow/nodes/agent/panel.spec.tsx
new file mode 100644
index 0000000000..1884a4dc0e
--- /dev/null
+++ b/web/app/components/workflow/nodes/agent/panel.spec.tsx
@@ -0,0 +1,176 @@
+/**
+ * Agent Panel - Enable Human Clarification Test
+ *
+ * Tests the enable_human_clarification onChange handler in the agent panel.
+ * Covers panel.tsx line 114: setInputs({ ...inputs, enable_human_clarification: value })
+ *
+ * Strategy: Mock FormInputBoolean to capture and trigger its onChange callback directly,
+ * avoiding dependency on component's internal text/UI.
+ */
+
+import type { AgentNodeType } from './types'
+import { render } from '@testing-library/react'
+import { beforeEach, describe, expect, it, vi } from 'vitest'
+import AgentPanel from './panel'
+
+// Mock setInputs at the top level
+const mockSetInputs = vi.fn()
+
+// Stub for panelProps - using any to avoid complex type requirements in test
+// eslint-disable-next-line ts/no-explicit-any
+const mockPanelProps = {} as any
+
+// Capture FormInputBoolean's onChange callback
+let capturedOnChange: ((value: boolean) => void) | null = null
+
+// Mock useConfig to return minimal required data
+vi.mock('./use-config', () => ({
+  default: () => ({
+    inputs: {
+      enable_human_clarification: false,
+      agent_strategy_name: 'test-strategy',
+      agent_strategy_provider_name: 'test-provider',
+      agent_strategy_label: 'Test Strategy',
+      meta: { version: '1.0' },
+      agent_parameters: {},
+      output_schema: {},
+      memory: undefined,
+    },
+    setInputs: mockSetInputs,
+    currentStrategy: null,
+    formData: {},
+    onFormChange: vi.fn(),
+    isChatMode: false,
+    availableNodesWithParent: [],
+    availableVars: [],
+    readOnly: false,
+    outputSchema: [],
+    handleMemoryChange: vi.fn(),
+  }),
+}))
+
+// Mock i18n
+vi.mock('react-i18next', () => ({
+  useTranslation: () => ({
+    t: (key: string) => key,
+  }),
+}))
+
+// Mock store
+vi.mock('../../store', () => ({
+  useStore: (selector: (state: Record<string, unknown>) => unknown) => {
+    const state = {
+      setControlPromptEditorRerenderKey: vi.fn(),
+    }
+    return selector(state)
+  },
+}))
+
+// Mock utility
+vi.mock('@/utils/plugin-version-feature', () => ({
+  isSupportMCP: () => true,
+}))
+
+// Mock heavy components
+vi.mock('../_base/components/agent-strategy', () => ({
+  AgentStrategy: () => <div />,
+}))
+
+vi.mock('../_base/components/mcp-tool-availability', () => ({
+  MCPToolAvailabilityProvider: ({ children }: { children: React.ReactNode }) => <>{children}</>,
+}))
+
+vi.mock('../_base/components/memory-config', () => ({
+  default: () => <div />,
+}))
+
+vi.mock('../_base/components/output-vars', () => ({
+  default: ({ children }: { children: React.ReactNode }) => <>{children}</>,
+  VarItem: () => <div />,
+}))
+
+vi.mock('../_base/components/split', () => ({
+  default: () => <div />,
+}))
+
+// Mock FormInputBoolean to capture onChange callback
+vi.mock('../_base/components/form-input-boolean', () => ({
+  default: ({ onChange }: { value: boolean, onChange: (value: boolean) => void }) => {
+    capturedOnChange = onChange
+    return <div data-testid="form-input-boolean" />
+  },
+}))
+
+describe('AgentPanel - Enable Human Clarification', () => {
+  beforeEach(() => {
+    mockSetInputs.mockClear()
+    capturedOnChange = null
+  })
+
+  it('should call setInputs with enable_human_clarification=true when onChange is triggered with true', () => {
+    const mockData = {} as AgentNodeType
+
+    render(
+      <AgentPanel
+        id="test-node"
+        data={mockData}
+        panelProps={mockPanelProps}
+      />,
+    )
+
+    // Trigger the captured onChange callback
+    capturedOnChange?.(true)
+
+    expect(mockSetInputs).toHaveBeenCalledWith(
+      expect.objectContaining({
+        enable_human_clarification: true,
+      }),
+    )
+  })
+
+  it('should call setInputs with enable_human_clarification=false when onChange is triggered with false', () => {
+    const mockData = {} as AgentNodeType
+
+    render(
+      <AgentPanel
+        id="test-node"
+        data={mockData}
+        panelProps={mockPanelProps}
+      />,
+    )
+
+    // Trigger the captured onChange callback
+    capturedOnChange?.(false)
+
+    expect(mockSetInputs).toHaveBeenCalledWith(
+      expect.objectContaining({
+        enable_human_clarification: false,
+      }),
+    )
+  })
+
+  it('should preserve other inputs when updating enable_human_clarification', () => {
+    const mockData = {} as AgentNodeType
+
+    render(
+      <AgentPanel
+        id="test-node"
+        data={mockData}
+        panelProps={mockPanelProps}
+      />,
+    )
+
+    // Trigger the captured onChange callback
+    capturedOnChange?.(true)
+
+    // Verify that spread operator preserves other inputs
+    expect(mockSetInputs).toHaveBeenCalledWith(
+      expect.objectContaining({
+        agent_strategy_name: 'test-strategy',
+        agent_strategy_provider_name: 'test-provider',
+        agent_strategy_label: 'Test Strategy',
+        enable_human_clarification: true,
+      }),
+    )
+  })
+})
diff --git a/web/app/components/workflow/nodes/agent/panel.tsx b/web/app/components/workflow/nodes/agent/panel.tsx
index 03e3aafa49..cd98d8604a 100644
--- a/web/app/components/workflow/nodes/agent/panel.tsx
+++ b/web/app/components/workflow/nodes/agent/panel.tsx
@@ -10,6 +10,7 @@ import { isSupportMCP } from '@/utils/plugin-version-feature'
 import { useStore } from '../../store'
 import { AgentStrategy } from '../_base/components/agent-strategy'
 import Field from '../_base/components/field'
+import FormInputBoolean from '../_base/components/form-input-boolean'
 import { MCPToolAvailabilityProvider } from '../_base/components/mcp-tool-availability'
 import MemoryConfig from '../_base/components/memory-config'
 import OutputVars, { VarItem } from '../_base/components/output-vars'
@@ -101,6 +102,22 @@ const AgentPanel: FC<NodePanelProps<AgentNodeType>> = (props) => {
             />
           </>
         )}
+        <Split />
+        <Field
+          title={t('nodes.agent.enableHumanClarification.label', { ns: 'workflow' })}
+          tooltip={t('nodes.agent.enableHumanClarification.tooltip', { ns: 'workflow' })}
+          className="px-0 py-2"
+        >
+          <FormInputBoolean
+            value={inputs.enable_human_clarification ?? false}
+            onChange={(value) => {
+              setInputs({
+                ...inputs,
+                enable_human_clarification: value,
+              })
+            }}
+          />
+        </Field>
       </div>
       <div>
         <OutputVars>
diff --git a/web/app/components/workflow/nodes/agent/types.ts b/web/app/components/workflow/nodes/agent/types.ts
index efc7c0cd9a..280beb9507 100644
--- a/web/app/components/workflow/nodes/agent/types.ts
+++ b/web/app/components/workflow/nodes/agent/types.ts
@@ -13,6 +13,7 @@ export type AgentNodeType = CommonNodeType & {
   memory?: Memory
   version?: string
   tool_node_version?: string
+  enable_human_clarification?: boolean
 }
 
 export enum AgentFeature {
diff --git a/web/i18n/en-US/workflow.json b/web/i18n/en-US/workflow.json
index 3bb285d501..bfcb9ab053 100644
--- a/web/i18n/en-US/workflow.json
+++ b/web/i18n/en-US/workflow.json
@@ -369,6 +369,8 @@
   "nodes.agent.checkList.strategyNotSelected": "Strategy not selected",
   "nodes.agent.clickToViewParameterSchema": "Click to view parameter schema",
   "nodes.agent.configureModel": "Configure Model",
+  "nodes.agent.enableHumanClarification.label": "Enable Human Clarification",
+  "nodes.agent.enableHumanClarification.tooltip": "Allow human intervention to clarify agent reasoning during execution",
   "nodes.agent.installPlugin.cancel": "Cancel",
   "nodes.agent.installPlugin.changelog": "Change log",
   "nodes.agent.installPlugin.desc": "About to install the following plugin",