🦥 feat: Add Deferred Tools as Agents Capability (#11295)

api/server/services/ToolService.js

@@ -409,8 +409,14 @@ async function loadAgentTools({
   const checkCapability = (capability) => {
     const enabled = enabledCapabilities.has(capability);
     if (!enabled) {
+      const isToolCapability = [
+        AgentCapabilities.file_search,
+        AgentCapabilities.execute_code,
+        AgentCapabilities.web_search,
+      ].includes(capability);
+      const suffix = isToolCapability ? ' despite configured tool.' : '.';
       logger.warn(
-        `Capability "${capability}" disabled${capability === AgentCapabilities.tools ? '.' : ' despite configured tool.'} User: ${req.user.id} | Agent: ${agent.id}`,
+        `Capability "${capability}" disabled${suffix} User: ${req.user.id} | Agent: ${agent.id}`,
       );
     }
     return enabled;
@@ -519,11 +525,13 @@ async function loadAgentTools({
   }, {});
 
   /** Build tool registry from MCP tools and create PTC/tool search tools if configured */
+  const deferredToolsEnabled = checkCapability(AgentCapabilities.deferred_tools);
   const { toolRegistry, additionalTools, hasDeferredTools } = await buildToolClassification({
     loadedTools,
     userId: req.user.id,
     agentId: agent.id,
     agentToolOptions: agent.tool_options,
+    deferredToolsEnabled,
     loadAuthValues,
   });
   agentTools.push(...additionalTools);

api/server/services/__tests__/ToolService.spec.js

@@ -0,0 +1,149 @@
+const { AgentCapabilities, defaultAgentCapabilities } = require('librechat-data-provider');
+
+/**
+ * Tests for ToolService capability checking logic.
+ * The actual loadAgentTools function has many dependencies, so we test
+ * the capability checking logic in isolation.
+ */
+describe('ToolService - Capability Checking', () => {
+  describe('checkCapability logic', () => {
+    /**
+     * Simulates the checkCapability function from loadAgentTools
+     */
+    const createCheckCapability = (enabledCapabilities, logger = { warn: jest.fn() }) => {
+      return (capability) => {
+        const enabled = enabledCapabilities.has(capability);
+        if (!enabled) {
+          const isToolCapability = [
+            AgentCapabilities.file_search,
+            AgentCapabilities.execute_code,
+            AgentCapabilities.web_search,
+          ].includes(capability);
+          const suffix = isToolCapability ? ' despite configured tool.' : '.';
+          logger.warn(`Capability "${capability}" disabled${suffix}`);
+        }
+        return enabled;
+      };
+    };
+
+    it('should return true when capability is enabled', () => {
+      const enabledCapabilities = new Set([AgentCapabilities.deferred_tools]);
+      const checkCapability = createCheckCapability(enabledCapabilities);
+
+      expect(checkCapability(AgentCapabilities.deferred_tools)).toBe(true);
+    });
+
+    it('should return false when capability is not enabled', () => {
+      const enabledCapabilities = new Set([]);
+      const checkCapability = createCheckCapability(enabledCapabilities);
+
+      expect(checkCapability(AgentCapabilities.deferred_tools)).toBe(false);
+    });
+
+    it('should log warning with "despite configured tool" for tool capabilities', () => {
+      const logger = { warn: jest.fn() };
+      const enabledCapabilities = new Set([]);
+      const checkCapability = createCheckCapability(enabledCapabilities, logger);
+
+      checkCapability(AgentCapabilities.file_search);
+      expect(logger.warn).toHaveBeenCalledWith(expect.stringContaining('despite configured tool'));
+
+      logger.warn.mockClear();
+      checkCapability(AgentCapabilities.execute_code);
+      expect(logger.warn).toHaveBeenCalledWith(expect.stringContaining('despite configured tool'));
+
+      logger.warn.mockClear();
+      checkCapability(AgentCapabilities.web_search);
+      expect(logger.warn).toHaveBeenCalledWith(expect.stringContaining('despite configured tool'));
+    });
+
+    it('should log warning without "despite configured tool" for non-tool capabilities', () => {
+      const logger = { warn: jest.fn() };
+      const enabledCapabilities = new Set([]);
+      const checkCapability = createCheckCapability(enabledCapabilities, logger);
+
+      checkCapability(AgentCapabilities.deferred_tools);
+      expect(logger.warn).toHaveBeenCalledWith(
+        expect.stringContaining('Capability "deferred_tools" disabled.'),
+      );
+      expect(logger.warn).not.toHaveBeenCalledWith(
+        expect.stringContaining('despite configured tool'),
+      );
+
+      logger.warn.mockClear();
+      checkCapability(AgentCapabilities.tools);
+      expect(logger.warn).toHaveBeenCalledWith(
+        expect.stringContaining('Capability "tools" disabled.'),
+      );
+      expect(logger.warn).not.toHaveBeenCalledWith(
+        expect.stringContaining('despite configured tool'),
+      );
+
+      logger.warn.mockClear();
+      checkCapability(AgentCapabilities.actions);
+      expect(logger.warn).toHaveBeenCalledWith(
+        expect.stringContaining('Capability "actions" disabled.'),
+      );
+    });
+
+    it('should not log warning when capability is enabled', () => {
+      const logger = { warn: jest.fn() };
+      const enabledCapabilities = new Set([
+        AgentCapabilities.deferred_tools,
+        AgentCapabilities.file_search,
+      ]);
+      const checkCapability = createCheckCapability(enabledCapabilities, logger);
+
+      checkCapability(AgentCapabilities.deferred_tools);
+      checkCapability(AgentCapabilities.file_search);
+
+      expect(logger.warn).not.toHaveBeenCalled();
+    });
+  });
+
+  describe('defaultAgentCapabilities', () => {
+    it('should include deferred_tools capability by default', () => {
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.deferred_tools);
+    });
+
+    it('should include all expected default capabilities', () => {
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.execute_code);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.file_search);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.web_search);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.artifacts);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.actions);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.context);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.tools);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.chain);
+      expect(defaultAgentCapabilities).toContain(AgentCapabilities.ocr);
+    });
+  });
+
+  describe('deferredToolsEnabled integration', () => {
+    it('should correctly determine deferredToolsEnabled from capabilities set', () => {
+      const createCheckCapability = (enabledCapabilities) => {
+        return (capability) => enabledCapabilities.has(capability);
+      };
+
+      // When deferred_tools is in capabilities
+      const withDeferred = new Set([AgentCapabilities.deferred_tools, AgentCapabilities.tools]);
+      const checkWithDeferred = createCheckCapability(withDeferred);
+      expect(checkWithDeferred(AgentCapabilities.deferred_tools)).toBe(true);
+
+      // When deferred_tools is NOT in capabilities
+      const withoutDeferred = new Set([AgentCapabilities.tools, AgentCapabilities.actions]);
+      const checkWithoutDeferred = createCheckCapability(withoutDeferred);
+      expect(checkWithoutDeferred(AgentCapabilities.deferred_tools)).toBe(false);
+    });
+
+    it('should use defaultAgentCapabilities when no capabilities configured', () => {
+      // Simulates the fallback behavior in loadAgentTools
+      const endpointsConfig = {}; // No capabilities configured
+      const enabledCapabilities = new Set(
+        endpointsConfig?.capabilities ?? defaultAgentCapabilities,
+      );
+
+      expect(enabledCapabilities.has(AgentCapabilities.deferred_tools)).toBe(true);
+    });
+  });
+});

client/src/components/SidePanel/Agents/MCPTool.tsx

@@ -1,9 +1,8 @@
 import React, { useState, useCallback } from 'react';
 import { ChevronDown, Clock } from 'lucide-react';
-import { useFormContext, useWatch } from 'react-hook-form';
 import { Constants } from 'librechat-data-provider';
+import { useFormContext, useWatch } from 'react-hook-form';
 import * as AccordionPrimitive from '@radix-ui/react-accordion';
-import type { AgentToolOptions } from 'librechat-data-provider';
 import {
   Label,
   ESide,
@@ -18,8 +17,15 @@ import {
   AccordionContent,
   OGDialogTemplate,
 } from '@librechat/client';
+import type { AgentToolOptions } from 'librechat-data-provider';
 import type { AgentForm, MCPServerInfo } from '~/common';
-import { useLocalize, useMCPServerManager, useRemoveMCPTool } from '~/hooks';
+import {
+  useAgentCapabilities,
+  useMCPServerManager,
+  useGetAgentsConfig,
+  useRemoveMCPTool,
+  useLocalize,
+} from '~/hooks';
 import MCPServerStatusIcon from '~/components/MCP/MCPServerStatusIcon';
 import MCPConfigDialog from '~/components/MCP/MCPConfigDialog';
 import { cn } from '~/utils';
@@ -29,6 +35,8 @@ export default function MCPTool({ serverInfo }: { serverInfo?: MCPServerInfo })
   const { removeTool } = useRemoveMCPTool();
   const { getValues, setValue, control } = useFormContext<AgentForm>();
   const { getServerStatusIconProps, getConfigDialogProps } = useMCPServerManager();
+  const { agentsConfig } = useGetAgentsConfig();
+  const { deferredToolsEnabled } = useAgentCapabilities(agentsConfig?.capabilities);
 
   const [isFocused, setIsFocused] = useState(false);
   const [isHovering, setIsHovering] = useState(false);
@@ -242,45 +250,47 @@ export default function MCPTool({ serverInfo }: { serverInfo?: MCPServerInfo })
                         </div>
 
                         {/* Defer All toggle - icon only with tooltip */}
-                        <TooltipAnchor
+                        {deferredToolsEnabled && (
-                          description={
+                          <TooltipAnchor
-                            areAllToolsDeferred
+                            description={
-                              ? localize('com_ui_mcp_undefer_all')
+                              areAllToolsDeferred
-                              : localize('com_ui_mcp_defer_all')
+                                ? localize('com_ui_mcp_undefer_all')
-                          }
+                                : localize('com_ui_mcp_defer_all')
-                          side="top"
+                            }
-                          role="button"
+                            side="top"
-                          tabIndex={isExpanded ? 0 : -1}
+                            role="button"
-                          aria-label={
+                            tabIndex={isExpanded ? 0 : -1}
-                            areAllToolsDeferred
+                            aria-label={
-                              ? localize('com_ui_mcp_undefer_all')
+                              areAllToolsDeferred
-                              : localize('com_ui_mcp_defer_all')
+                                ? localize('com_ui_mcp_undefer_all')
-                          }
+                                : localize('com_ui_mcp_defer_all')
-                          aria-pressed={areAllToolsDeferred}
+                            }
-                          className={cn(
+                            aria-pressed={areAllToolsDeferred}
-                            'flex h-7 w-7 items-center justify-center rounded transition-colors duration-200',
+                            className={cn(
-                            'focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-1',
+                              'flex h-7 w-7 items-center justify-center rounded transition-colors duration-200',
-                            isExpanded ? 'visible' : 'pointer-events-none invisible',
+                              'focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-1',
-                            areAllToolsDeferred
+                              isExpanded ? 'visible' : 'pointer-events-none invisible',
-                              ? 'bg-amber-500/20 text-amber-500 hover:bg-amber-500/30'
+                              areAllToolsDeferred
-                              : 'text-text-tertiary hover:bg-surface-hover hover:text-text-primary',
+                                ? 'bg-amber-500/20 text-amber-500 hover:bg-amber-500/30'
-                          )}
+                                : 'text-text-tertiary hover:bg-surface-hover hover:text-text-primary',
-                          onClick={(e) => {
+                            )}
-                            e.stopPropagation();
+                            onClick={(e) => {
-                            toggleDeferAll();
-                          }}
-                          onKeyDown={(e) => {
-                            if (e.key === 'Enter' || e.key === ' ') {
-                              e.preventDefault();
                               e.stopPropagation();
                               toggleDeferAll();
-                            }
+                            }}
-                          }}
+                            onKeyDown={(e) => {
-                        >
+                              if (e.key === 'Enter' || e.key === ' ') {
-                          <Clock
+                                e.preventDefault();
-                            className={cn('h-4 w-4', areAllToolsDeferred && 'fill-amber-500/30')}
+                                e.stopPropagation();
-                          />
+                                toggleDeferAll();
-                        </TooltipAnchor>
+                              }
+                            }}
+                          >
+                            <Clock
+                              className={cn('h-4 w-4', areAllToolsDeferred && 'fill-amber-500/30')}
+                            />
+                          </TooltipAnchor>
+                        )}
 
                         <div className="flex items-center gap-1">
                           {/* Caret button for accordion */}
@@ -343,7 +353,7 @@ export default function MCPTool({ serverInfo }: { serverInfo?: MCPServerInfo })
           <AccordionContent className="relative ml-1 pt-1 before:absolute before:bottom-2 before:left-0 before:top-0 before:w-0.5 before:bg-border-medium">
             <div className="space-y-1">
               {serverInfo.tools?.map((subTool) => {
-                const isDeferred = isToolDeferred(subTool.tool_id);
+                const isDeferred = deferredToolsEnabled && isToolDeferred(subTool.tool_id);
                 return (
                   <label
                     key={subTool.tool_id}
@@ -388,42 +398,44 @@ export default function MCPTool({ serverInfo }: { serverInfo?: MCPServerInfo })
                     </span>
                     <div className="ml-auto flex items-center gap-1">
                       {/* Per-tool defer toggle - icon only */}
-                      <TooltipAnchor
+                      {deferredToolsEnabled && (
-                        description={
+                        <TooltipAnchor
-                          isDeferred
+                          description={
-                            ? localize('com_ui_mcp_click_to_undefer')
+                            isDeferred
-                            : localize('com_ui_mcp_click_to_defer')
+                              ? localize('com_ui_mcp_click_to_undefer')
-                        }
+                              : localize('com_ui_mcp_click_to_defer')
-                        side="top"
+                          }
-                        role="button"
+                          side="top"
-                        aria-label={
+                          role="button"
-                          isDeferred
+                          aria-label={
-                            ? localize('com_ui_mcp_undefer')
+                            isDeferred
-                            : localize('com_ui_mcp_defer_loading')
+                              ? localize('com_ui_mcp_undefer')
-                        }
+                              : localize('com_ui_mcp_defer_loading')
-                        aria-pressed={isDeferred}
+                          }
-                        className={cn(
+                          aria-pressed={isDeferred}
-                          'flex h-6 w-6 items-center justify-center rounded transition-all duration-200',
+                          className={cn(
-                          'focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-1',
+                            'flex h-6 w-6 items-center justify-center rounded transition-all duration-200',
-                          isDeferred
+                            'focus:outline-none focus:ring-2 focus:ring-ring focus:ring-offset-1',
-                            ? 'bg-amber-500/20 text-amber-500 hover:bg-amber-500/30'
+                            isDeferred
-                            : 'text-text-tertiary opacity-0 hover:bg-surface-hover hover:text-text-primary group-focus-within/item:opacity-100 group-hover/item:opacity-100',
+                              ? 'bg-amber-500/20 text-amber-500 hover:bg-amber-500/30'
-                        )}
+                              : 'text-text-tertiary opacity-0 hover:bg-surface-hover hover:text-text-primary group-focus-within/item:opacity-100 group-hover/item:opacity-100',
-                        onClick={(e) => {
+                          )}
-                          e.stopPropagation();
+                          onClick={(e) => {
-                          e.preventDefault();
+                            e.stopPropagation();
-                          toggleToolDefer(subTool.tool_id);
-                        }}
-                        onKeyDown={(e) => {
-                          e.stopPropagation();
-                          if (e.key === 'Enter' || e.key === ' ') {
                             e.preventDefault();
                             toggleToolDefer(subTool.tool_id);
-                          }
+                          }}
-                        }}
+                          onKeyDown={(e) => {
-                      >
+                            e.stopPropagation();
-                        <Clock className={cn('h-3.5 w-3.5', isDeferred && 'fill-amber-500/30')} />
+                            if (e.key === 'Enter' || e.key === ' ') {
-                      </TooltipAnchor>
+                              e.preventDefault();
+                              toggleToolDefer(subTool.tool_id);
+                            }
+                          }}
+                        >
+                          <Clock className={cn('h-3.5 w-3.5', isDeferred && 'fill-amber-500/30')} />
+                        </TooltipAnchor>
+                      )}
                       {subTool.metadata.description && (
                         <InfoHoverCard side={ESide.Left} text={subTool.metadata.description} />
                       )}

client/src/hooks/Agents/__tests__/useAgentCapabilities.spec.ts

@@ -0,0 +1,88 @@
+import { renderHook } from '@testing-library/react';
+import { AgentCapabilities } from 'librechat-data-provider';
+import useAgentCapabilities from '../useAgentCapabilities';
+
+describe('useAgentCapabilities', () => {
+  it('should return all capabilities as false when capabilities is undefined', () => {
+    const { result } = renderHook(() => useAgentCapabilities(undefined));
+
+    expect(result.current.toolsEnabled).toBe(false);
+    expect(result.current.actionsEnabled).toBe(false);
+    expect(result.current.artifactsEnabled).toBe(false);
+    expect(result.current.ocrEnabled).toBe(false);
+    expect(result.current.contextEnabled).toBe(false);
+    expect(result.current.fileSearchEnabled).toBe(false);
+    expect(result.current.webSearchEnabled).toBe(false);
+    expect(result.current.codeEnabled).toBe(false);
+    expect(result.current.deferredToolsEnabled).toBe(false);
+  });
+
+  it('should return all capabilities as false when capabilities is empty array', () => {
+    const { result } = renderHook(() => useAgentCapabilities([]));
+
+    expect(result.current.toolsEnabled).toBe(false);
+    expect(result.current.deferredToolsEnabled).toBe(false);
+  });
+
+  it('should return true for enabled capabilities', () => {
+    const capabilities = [
+      AgentCapabilities.tools,
+      AgentCapabilities.deferred_tools,
+      AgentCapabilities.file_search,
+    ];
+
+    const { result } = renderHook(() => useAgentCapabilities(capabilities));
+
+    expect(result.current.toolsEnabled).toBe(true);
+    expect(result.current.deferredToolsEnabled).toBe(true);
+    expect(result.current.fileSearchEnabled).toBe(true);
+    expect(result.current.actionsEnabled).toBe(false);
+    expect(result.current.webSearchEnabled).toBe(false);
+  });
+
+  it('should return deferredToolsEnabled as true when deferred_tools is in capabilities', () => {
+    const capabilities = [AgentCapabilities.deferred_tools];
+
+    const { result } = renderHook(() => useAgentCapabilities(capabilities));
+
+    expect(result.current.deferredToolsEnabled).toBe(true);
+  });
+
+  it('should return deferredToolsEnabled as false when deferred_tools is not in capabilities', () => {
+    const capabilities = [
+      AgentCapabilities.tools,
+      AgentCapabilities.actions,
+      AgentCapabilities.artifacts,
+    ];
+
+    const { result } = renderHook(() => useAgentCapabilities(capabilities));
+
+    expect(result.current.deferredToolsEnabled).toBe(false);
+  });
+
+  it('should handle all capabilities being enabled', () => {
+    const capabilities = [
+      AgentCapabilities.tools,
+      AgentCapabilities.actions,
+      AgentCapabilities.artifacts,
+      AgentCapabilities.ocr,
+      AgentCapabilities.context,
+      AgentCapabilities.file_search,
+      AgentCapabilities.web_search,
+      AgentCapabilities.execute_code,
+      AgentCapabilities.deferred_tools,
+    ];
+
+    const { result } = renderHook(() => useAgentCapabilities(capabilities));
+
+    expect(result.current.toolsEnabled).toBe(true);
+    expect(result.current.actionsEnabled).toBe(true);
+    expect(result.current.artifactsEnabled).toBe(true);
+    expect(result.current.ocrEnabled).toBe(true);
+    expect(result.current.contextEnabled).toBe(true);
+    expect(result.current.fileSearchEnabled).toBe(true);
+    expect(result.current.webSearchEnabled).toBe(true);
+    expect(result.current.codeEnabled).toBe(true);
+    expect(result.current.deferredToolsEnabled).toBe(true);
+  });
+});

client/src/hooks/Agents/useAgentCapabilities.ts

@@ -10,6 +10,7 @@ interface AgentCapabilitiesResult {
   fileSearchEnabled: boolean;
   webSearchEnabled: boolean;
   codeEnabled: boolean;
+  deferredToolsEnabled: boolean;
 }
 
 export default function useAgentCapabilities(
@@ -55,6 +56,11 @@ export default function useAgentCapabilities(
     [capabilities],
   );
 
+  const deferredToolsEnabled = useMemo(
+    () => capabilities?.includes(AgentCapabilities.deferred_tools) ?? false,
+    [capabilities],
+  );
+
   return {
     ocrEnabled,
     codeEnabled,
@@ -64,5 +70,6 @@ export default function useAgentCapabilities(
     artifactsEnabled,
     webSearchEnabled,
     fileSearchEnabled,
+    deferredToolsEnabled,
   };
 }

packages/api/src/tools/classification.spec.ts

@@ -0,0 +1,453 @@
+import {
+  parseToolList,
+  toolMatchesPatterns,
+  getServerNameFromTool,
+  buildToolRegistryFromEnv,
+  buildToolRegistryFromAgentOptions,
+  buildToolClassification,
+  agentHasDeferredTools,
+  agentHasProgrammaticTools,
+  isAgentAllowedForClassification,
+} from './classification';
+import type { ToolDefinition, LCToolRegistry } from './classification';
+import type { GenericTool } from '@librechat/agents';
+import type { AgentToolOptions } from 'librechat-data-provider';
+
+describe('classification.ts', () => {
+  const originalEnv = process.env;
+
+  beforeEach(() => {
+    process.env = { ...originalEnv };
+    // Clear classification-related env vars
+    delete process.env.TOOL_PROGRAMMATIC_ONLY;
+    delete process.env.TOOL_PROGRAMMATIC_ONLY_EXCLUDE;
+    delete process.env.TOOL_DUAL_CONTEXT;
+    delete process.env.TOOL_DUAL_CONTEXT_EXCLUDE;
+    delete process.env.TOOL_DEFERRED;
+    delete process.env.TOOL_DEFERRED_EXCLUDE;
+    delete process.env.TOOL_CLASSIFICATION_AGENT_IDS;
+    delete process.env.TOOL_CLASSIFICATION_FROM_ENV;
+  });
+
+  afterEach(() => {
+    process.env = originalEnv;
+  });
+
+  describe('parseToolList', () => {
+    it('should return empty set for undefined input', () => {
+      const result = parseToolList(undefined);
+      expect(result.size).toBe(0);
+    });
+
+    it('should return empty set for empty string', () => {
+      const result = parseToolList('');
+      expect(result.size).toBe(0);
+    });
+
+    it('should return empty set for whitespace-only string', () => {
+      const result = parseToolList('   ');
+      expect(result.size).toBe(0);
+    });
+
+    it('should parse comma-separated tool names', () => {
+      const result = parseToolList('tool1,tool2,tool3');
+      expect(result.size).toBe(3);
+      expect(result.has('tool1')).toBe(true);
+      expect(result.has('tool2')).toBe(true);
+      expect(result.has('tool3')).toBe(true);
+    });
+
+    it('should trim whitespace from tool names', () => {
+      const result = parseToolList('  tool1  ,  tool2  ');
+      expect(result.size).toBe(2);
+      expect(result.has('tool1')).toBe(true);
+      expect(result.has('tool2')).toBe(true);
+    });
+
+    it('should filter out empty entries', () => {
+      const result = parseToolList('tool1,,tool2,,,tool3');
+      expect(result.size).toBe(3);
+    });
+  });
+
+  describe('getServerNameFromTool', () => {
+    it('should extract server name from MCP tool name', () => {
+      const result = getServerNameFromTool('list_files_mcp_Google-Workspace');
+      expect(result).toBe('Google-Workspace');
+    });
+
+    it('should return undefined for non-MCP tool', () => {
+      const result = getServerNameFromTool('simple_tool');
+      expect(result).toBeUndefined();
+    });
+
+    it('should handle multiple delimiters', () => {
+      const result = getServerNameFromTool('some_tool_mcp_Server_Name');
+      expect(result).toBe('Server_Name');
+    });
+  });
+
+  describe('toolMatchesPatterns', () => {
+    it('should return true for exact match', () => {
+      const patterns = new Set(['tool1', 'tool2']);
+      const excludes = new Set<string>();
+      expect(toolMatchesPatterns('tool1', patterns, excludes)).toBe(true);
+    });
+
+    it('should return false for non-matching tool', () => {
+      const patterns = new Set(['tool1', 'tool2']);
+      const excludes = new Set<string>();
+      expect(toolMatchesPatterns('tool3', patterns, excludes)).toBe(false);
+    });
+
+    it('should return false when tool is in excludes', () => {
+      const patterns = new Set(['tool1', 'tool2']);
+      const excludes = new Set(['tool1']);
+      expect(toolMatchesPatterns('tool1', patterns, excludes)).toBe(false);
+    });
+
+    it('should match server-wide pattern', () => {
+      const patterns = new Set(['sys__all__sys_mcp_Google-Workspace']);
+      const excludes = new Set<string>();
+      expect(toolMatchesPatterns('list_files_mcp_Google-Workspace', patterns, excludes)).toBe(true);
+    });
+
+    it('should respect excludes for server-wide patterns', () => {
+      const patterns = new Set(['sys__all__sys_mcp_Google-Workspace']);
+      const excludes = new Set(['list_files_mcp_Google-Workspace']);
+      expect(toolMatchesPatterns('list_files_mcp_Google-Workspace', patterns, excludes)).toBe(
+        false,
+      );
+    });
+  });
+
+  describe('buildToolRegistryFromEnv', () => {
+    it('should set defer_loading based on TOOL_DEFERRED env var', () => {
+      process.env.TOOL_DEFERRED = 'tool1,tool2';
+
+      const tools: ToolDefinition[] = [
+        { name: 'tool1', description: 'Tool 1' },
+        { name: 'tool2', description: 'Tool 2' },
+        { name: 'tool3', description: 'Tool 3' },
+      ];
+
+      const registry = buildToolRegistryFromEnv(tools);
+
+      expect(registry.get('tool1')?.defer_loading).toBe(true);
+      expect(registry.get('tool2')?.defer_loading).toBe(true);
+      expect(registry.get('tool3')?.defer_loading).toBe(false);
+    });
+
+    it('should respect TOOL_DEFERRED_EXCLUDE', () => {
+      process.env.TOOL_DEFERRED = 'sys__all__sys_mcp_TestServer';
+      process.env.TOOL_DEFERRED_EXCLUDE = 'tool2_mcp_TestServer';
+
+      const tools: ToolDefinition[] = [
+        { name: 'tool1_mcp_TestServer', description: 'Tool 1' },
+        { name: 'tool2_mcp_TestServer', description: 'Tool 2' },
+      ];
+
+      const registry = buildToolRegistryFromEnv(tools);
+
+      expect(registry.get('tool1_mcp_TestServer')?.defer_loading).toBe(true);
+      expect(registry.get('tool2_mcp_TestServer')?.defer_loading).toBe(false);
+    });
+
+    it('should set allowed_callers based on TOOL_PROGRAMMATIC_ONLY', () => {
+      process.env.TOOL_PROGRAMMATIC_ONLY = 'tool1';
+
+      const tools: ToolDefinition[] = [
+        { name: 'tool1', description: 'Tool 1' },
+        { name: 'tool2', description: 'Tool 2' },
+      ];
+
+      const registry = buildToolRegistryFromEnv(tools);
+
+      expect(registry.get('tool1')?.allowed_callers).toEqual(['code_execution']);
+      expect(registry.get('tool2')?.allowed_callers).toEqual(['direct']);
+    });
+
+    it('should set dual context callers based on TOOL_DUAL_CONTEXT', () => {
+      process.env.TOOL_DUAL_CONTEXT = 'tool1';
+
+      const tools: ToolDefinition[] = [{ name: 'tool1', description: 'Tool 1' }];
+
+      const registry = buildToolRegistryFromEnv(tools);
+
+      expect(registry.get('tool1')?.allowed_callers).toEqual(['direct', 'code_execution']);
+    });
+  });
+
+  describe('buildToolRegistryFromAgentOptions', () => {
+    it('should use agent tool options for defer_loading', () => {
+      const tools: ToolDefinition[] = [
+        { name: 'tool1', description: 'Tool 1' },
+        { name: 'tool2', description: 'Tool 2' },
+      ];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { defer_loading: true },
+        tool2: { defer_loading: false },
+      };
+
+      const registry = buildToolRegistryFromAgentOptions(tools, agentToolOptions);
+
+      expect(registry.get('tool1')?.defer_loading).toBe(true);
+      expect(registry.get('tool2')?.defer_loading).toBe(false);
+    });
+
+    it('should default defer_loading to false when not specified', () => {
+      const tools: ToolDefinition[] = [{ name: 'tool1', description: 'Tool 1' }];
+
+      const agentToolOptions: AgentToolOptions = {};
+
+      const registry = buildToolRegistryFromAgentOptions(tools, agentToolOptions);
+
+      expect(registry.get('tool1')?.defer_loading).toBe(false);
+    });
+
+    it('should use agent allowed_callers when specified', () => {
+      const tools: ToolDefinition[] = [{ name: 'tool1', description: 'Tool 1' }];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { allowed_callers: ['code_execution'] },
+      };
+
+      const registry = buildToolRegistryFromAgentOptions(tools, agentToolOptions);
+
+      expect(registry.get('tool1')?.allowed_callers).toEqual(['code_execution']);
+    });
+  });
+
+  describe('agentHasDeferredTools', () => {
+    it('should return true when registry has deferred tools', () => {
+      const registry: LCToolRegistry = new Map([
+        ['tool1', { name: 'tool1', allowed_callers: ['direct'], defer_loading: true }],
+        ['tool2', { name: 'tool2', allowed_callers: ['direct'], defer_loading: false }],
+      ]);
+
+      expect(agentHasDeferredTools(registry)).toBe(true);
+    });
+
+    it('should return false when no tools are deferred', () => {
+      const registry: LCToolRegistry = new Map([
+        ['tool1', { name: 'tool1', allowed_callers: ['direct'], defer_loading: false }],
+        ['tool2', { name: 'tool2', allowed_callers: ['direct'], defer_loading: false }],
+      ]);
+
+      expect(agentHasDeferredTools(registry)).toBe(false);
+    });
+
+    it('should return false for empty registry', () => {
+      const registry: LCToolRegistry = new Map();
+      expect(agentHasDeferredTools(registry)).toBe(false);
+    });
+  });
+
+  describe('agentHasProgrammaticTools', () => {
+    it('should return true when registry has programmatic tools', () => {
+      const registry: LCToolRegistry = new Map([
+        ['tool1', { name: 'tool1', allowed_callers: ['code_execution'], defer_loading: false }],
+      ]);
+
+      expect(agentHasProgrammaticTools(registry)).toBe(true);
+    });
+
+    it('should return true for dual context tools', () => {
+      const registry: LCToolRegistry = new Map([
+        [
+          'tool1',
+          { name: 'tool1', allowed_callers: ['direct', 'code_execution'], defer_loading: false },
+        ],
+      ]);
+
+      expect(agentHasProgrammaticTools(registry)).toBe(true);
+    });
+
+    it('should return false when no programmatic tools', () => {
+      const registry: LCToolRegistry = new Map([
+        ['tool1', { name: 'tool1', allowed_callers: ['direct'], defer_loading: false }],
+      ]);
+
+      expect(agentHasProgrammaticTools(registry)).toBe(false);
+    });
+  });
+
+  describe('isAgentAllowedForClassification', () => {
+    it('should return true when TOOL_CLASSIFICATION_AGENT_IDS is not set', () => {
+      expect(isAgentAllowedForClassification('any-agent-id')).toBe(true);
+    });
+
+    it('should return true when agent is in allowed list', () => {
+      process.env.TOOL_CLASSIFICATION_AGENT_IDS = 'agent1,agent2,agent3';
+      expect(isAgentAllowedForClassification('agent2')).toBe(true);
+    });
+
+    it('should return false when agent is not in allowed list', () => {
+      process.env.TOOL_CLASSIFICATION_AGENT_IDS = 'agent1,agent2';
+      expect(isAgentAllowedForClassification('agent3')).toBe(false);
+    });
+
+    it('should return false when agentId is undefined and list is set', () => {
+      process.env.TOOL_CLASSIFICATION_AGENT_IDS = 'agent1';
+      expect(isAgentAllowedForClassification(undefined)).toBe(false);
+    });
+  });
+
+  describe('buildToolClassification with deferredToolsEnabled', () => {
+    const mockLoadAuthValues = jest.fn().mockResolvedValue({});
+
+    const createMCPTool = (name: string, description?: string) =>
+      ({
+        name,
+        description,
+        mcp: true,
+        mcpJsonSchema: { type: 'object', properties: {} },
+      }) as unknown as GenericTool;
+
+    beforeEach(() => {
+      jest.clearAllMocks();
+    });
+
+    it('should return hasDeferredTools: false when deferredToolsEnabled is false', async () => {
+      const loadedTools: GenericTool[] = [createMCPTool('tool1'), createMCPTool('tool2')];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { defer_loading: true },
+        tool2: { defer_loading: true },
+      };
+
+      const result = await buildToolClassification({
+        loadedTools,
+        userId: 'user1',
+        agentId: 'agent1',
+        agentToolOptions,
+        deferredToolsEnabled: false,
+        loadAuthValues: mockLoadAuthValues,
+      });
+
+      expect(result.hasDeferredTools).toBe(false);
+      expect(result.additionalTools.length).toBe(0);
+    });
+
+    it('should clear defer_loading from all tools when deferredToolsEnabled is false', async () => {
+      const loadedTools: GenericTool[] = [createMCPTool('tool1'), createMCPTool('tool2')];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { defer_loading: true },
+        tool2: { defer_loading: true },
+      };
+
+      const result = await buildToolClassification({
+        loadedTools,
+        userId: 'user1',
+        agentId: 'agent1',
+        agentToolOptions,
+        deferredToolsEnabled: false,
+        loadAuthValues: mockLoadAuthValues,
+      });
+
+      expect(result.toolRegistry).toBeDefined();
+      expect(result.toolRegistry?.get('tool1')?.defer_loading).toBe(false);
+      expect(result.toolRegistry?.get('tool2')?.defer_loading).toBe(false);
+    });
+
+    it('should preserve defer_loading when deferredToolsEnabled is true', async () => {
+      const loadedTools: GenericTool[] = [createMCPTool('tool1'), createMCPTool('tool2')];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { defer_loading: true },
+        tool2: { defer_loading: false },
+      };
+
+      const result = await buildToolClassification({
+        loadedTools,
+        userId: 'user1',
+        agentId: 'agent1',
+        agentToolOptions,
+        deferredToolsEnabled: true,
+        loadAuthValues: mockLoadAuthValues,
+      });
+
+      expect(result.hasDeferredTools).toBe(true);
+      expect(result.toolRegistry?.get('tool1')?.defer_loading).toBe(true);
+      expect(result.toolRegistry?.get('tool2')?.defer_loading).toBe(false);
+    });
+
+    it('should create tool search when deferredToolsEnabled is true and has deferred tools', async () => {
+      const loadedTools: GenericTool[] = [createMCPTool('tool1')];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { defer_loading: true },
+      };
+
+      const result = await buildToolClassification({
+        loadedTools,
+        userId: 'user1',
+        agentId: 'agent1',
+        agentToolOptions,
+        deferredToolsEnabled: true,
+        loadAuthValues: mockLoadAuthValues,
+      });
+
+      expect(result.hasDeferredTools).toBe(true);
+      expect(result.additionalTools.some((t) => t.name === 'tool_search')).toBe(true);
+    });
+
+    it('should NOT create tool search when deferredToolsEnabled is false', async () => {
+      const loadedTools: GenericTool[] = [createMCPTool('tool1')];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { defer_loading: true },
+      };
+
+      const result = await buildToolClassification({
+        loadedTools,
+        userId: 'user1',
+        agentId: 'agent1',
+        agentToolOptions,
+        deferredToolsEnabled: false,
+        loadAuthValues: mockLoadAuthValues,
+      });
+
+      expect(result.hasDeferredTools).toBe(false);
+      expect(result.additionalTools.some((t) => t.name === 'tool_search')).toBe(false);
+    });
+
+    it('should default deferredToolsEnabled to true when not specified', async () => {
+      const loadedTools: GenericTool[] = [createMCPTool('tool1')];
+
+      const agentToolOptions: AgentToolOptions = {
+        tool1: { defer_loading: true },
+      };
+
+      const result = await buildToolClassification({
+        loadedTools,
+        userId: 'user1',
+        agentId: 'agent1',
+        agentToolOptions,
+        loadAuthValues: mockLoadAuthValues,
+      });
+
+      expect(result.hasDeferredTools).toBe(true);
+    });
+
+    it('should return early when no MCP tools are present', async () => {
+      const loadedTools: GenericTool[] = [
+        { name: 'regular_tool', mcp: false } as unknown as GenericTool,
+      ];
+
+      const result = await buildToolClassification({
+        loadedTools,
+        userId: 'user1',
+        agentId: 'agent1',
+        deferredToolsEnabled: true,
+        loadAuthValues: mockLoadAuthValues,
+      });
+
+      expect(result.toolRegistry).toBeUndefined();
+      expect(result.hasDeferredTools).toBe(false);
+      expect(result.additionalTools.length).toBe(0);
+    });
+  });
+});

packages/api/src/tools/classification.ts

@@ -322,6 +322,8 @@ export interface BuildToolClassificationParams {
   agentId?: string;
   /** Per-tool configuration from the agent (takes precedence over env vars) */
   agentToolOptions?: AgentToolOptions;
+  /** Whether the deferred_tools capability is enabled (from agent config) */
+  deferredToolsEnabled?: boolean;
   /** Function to load auth values (dependency injection) */
   loadAuthValues: (params: {
     userId: string;
@@ -404,7 +406,14 @@ export function agentHasDeferredTools(toolRegistry: LCToolRegistry): boolean {
 export async function buildToolClassification(
   params: BuildToolClassificationParams,
 ): Promise<BuildToolClassificationResult> {
-  const { loadedTools, userId, agentId, agentToolOptions, loadAuthValues } = params;
+  const {
+    loadedTools,
+    userId,
+    agentId,
+    agentToolOptions,
+    deferredToolsEnabled = true,
+    loadAuthValues,
+  } = params;
   const additionalTools: GenericTool[] = [];
 
   /** Check if this agent is allowed to have classification features (requires agentId) */
@@ -444,10 +453,22 @@ export async function buildToolClassification(
   /**
    * Check if this agent actually has tools that match the patterns.
    * Only enable PTC if the agent has programmatic tools.
-   * Only enable tool search if the agent has deferred tools.
+   * Only enable tool search if the agent has deferred tools AND the capability is enabled.
    */
   const hasProgrammaticTools = agentHasProgrammaticTools(toolRegistry);
-  const hasDeferredTools = agentHasDeferredTools(toolRegistry);
+  const hasDeferredTools = deferredToolsEnabled && agentHasDeferredTools(toolRegistry);
+
+  /**
+   * If deferred tools capability is disabled, clear defer_loading from all tools
+   * to ensure no tools are treated as deferred at runtime.
+   */
+  if (!deferredToolsEnabled) {
+    for (const toolDef of toolRegistry.values()) {
+      if (toolDef.defer_loading === true) {
+        toolDef.defer_loading = false;
+      }
+    }
+  }
 
   if (!hasProgrammaticTools && !hasDeferredTools) {
     logger.debug(

packages/data-provider/src/config.ts

@@ -177,6 +177,7 @@ export enum Capabilities {
 export enum AgentCapabilities {
   hide_sequential_outputs = 'hide_sequential_outputs',
   end_after_tools = 'end_after_tools',
+  deferred_tools = 'deferred_tools',
   execute_code = 'execute_code',
   file_search = 'file_search',
   web_search = 'web_search',
@@ -259,6 +260,7 @@ export const assistantEndpointSchema = baseEndpointSchema.merge(
 export type TAssistantEndpoint = z.infer<typeof assistantEndpointSchema>;
 
 export const defaultAgentCapabilities = [
+  AgentCapabilities.deferred_tools,
   AgentCapabilities.execute_code,
   AgentCapabilities.file_search,
   AgentCapabilities.web_search,