7 files changed, 609 insertions, 0 deletions
diff --git a/packages/cli/src/ui/commands/clearCommand.test.ts b/packages/cli/src/ui/commands/clearCommand.test.ts
new file mode 100644
index 00000000..8019dd68
--- /dev/null
+++ b/packages/cli/src/ui/commands/clearCommand.test.ts
@@ -0,0 +1,78 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { vi, describe, it, expect, beforeEach, Mock } from 'vitest';
+import { clearCommand } from './clearCommand.js';
+import { type CommandContext } from './types.js';
+import { createMockCommandContext } from '../../test-utils/mockCommandContext.js';
+import { GeminiClient } from '@google/gemini-cli-core';
+
+describe('clearCommand', () => {
+  let mockContext: CommandContext;
+  let mockResetChat: ReturnType<typeof vi.fn>;
+
+  beforeEach(() => {
+    mockResetChat = vi.fn().mockResolvedValue(undefined);
+
+    mockContext = createMockCommandContext({
+      services: {
+        config: {
+          getGeminiClient: () =>
+            ({
+              resetChat: mockResetChat,
+            }) as unknown as GeminiClient,
+        },
+      },
+    });
+  });
+
+  it('should set debug message, reset chat, and clear UI when config is available', async () => {
+    if (!clearCommand.action) {
+      throw new Error('clearCommand must have an action.');
+    }
+
+    await clearCommand.action(mockContext, '');
+
+    expect(mockContext.ui.setDebugMessage).toHaveBeenCalledWith(
+      'Clearing terminal and resetting chat.',
+    );
+    expect(mockContext.ui.setDebugMessage).toHaveBeenCalledTimes(1);
+
+    expect(mockResetChat).toHaveBeenCalledTimes(1);
+
+    expect(mockContext.ui.clear).toHaveBeenCalledTimes(1);
+
+    // Check the order of operations.
+    const setDebugMessageOrder = (mockContext.ui.setDebugMessage as Mock).mock
+      .invocationCallOrder[0];
+    const resetChatOrder = mockResetChat.mock.invocationCallOrder[0];
+    const clearOrder = (mockContext.ui.clear as Mock).mock
+      .invocationCallOrder[0];
+
+    expect(setDebugMessageOrder).toBeLessThan(resetChatOrder);
+    expect(resetChatOrder).toBeLessThan(clearOrder);
+  });
+
+  it('should not attempt to reset chat if config service is not available', async () => {
+    if (!clearCommand.action) {
+      throw new Error('clearCommand must have an action.');
+    }
+
+    const nullConfigContext = createMockCommandContext({
+      services: {
+        config: null,
+      },
+    });
+
+    await clearCommand.action(nullConfigContext, '');
+
+    expect(nullConfigContext.ui.setDebugMessage).toHaveBeenCalledWith(
+      'Clearing terminal and resetting chat.',
+    );
+    expect(mockResetChat).not.toHaveBeenCalled();
+    expect(nullConfigContext.ui.clear).toHaveBeenCalledTimes(1);
+  });
+});
diff --git a/packages/cli/src/ui/commands/clearCommand.ts b/packages/cli/src/ui/commands/clearCommand.ts
new file mode 100644
index 00000000..e5473b5b
--- /dev/null
+++ b/packages/cli/src/ui/commands/clearCommand.ts
@@ -0,0 +1,17 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { SlashCommand } from './types.js';
+
+export const clearCommand: SlashCommand = {
+  name: 'clear',
+  description: 'clear the screen and conversation history',
+  action: async (context, _args) => {
+    context.ui.setDebugMessage('Clearing terminal and resetting chat.');
+    await context.services.config?.getGeminiClient()?.resetChat();
+    context.ui.clear();
+  },
+};
diff --git a/packages/cli/src/ui/commands/helpCommand.test.ts b/packages/cli/src/ui/commands/helpCommand.test.ts
new file mode 100644
index 00000000..a6b19c05
--- /dev/null
+++ b/packages/cli/src/ui/commands/helpCommand.test.ts
@@ -0,0 +1,40 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { vi, describe, it, expect, beforeEach } from 'vitest';
+import { helpCommand } from './helpCommand.js';
+import { type CommandContext } from './types.js';
+
+describe('helpCommand', () => {
+  let mockContext: CommandContext;
+
+  beforeEach(() => {
+    mockContext = {} as unknown as CommandContext;
+  });
+
+  it("should return a dialog action and log a debug message for '/help'", () => {
+    const consoleDebugSpy = vi
+      .spyOn(console, 'debug')
+      .mockImplementation(() => {});
+    if (!helpCommand.action) {
+      throw new Error('Help command has no action');
+    }
+    const result = helpCommand.action(mockContext, '');
+
+    expect(result).toEqual({
+      type: 'dialog',
+      dialog: 'help',
+    });
+    expect(consoleDebugSpy).toHaveBeenCalledWith('Opening help UI ...');
+  });
+
+  it("should also be triggered by its alternative name '?'", () => {
+    // This test is more conceptual. The routing of altName to the command
+    // is handled by the slash command processor, but we can assert the
+    // altName is correctly defined on the command object itself.
+    expect(helpCommand.altName).toBe('?');
+  });
+});
diff --git a/packages/cli/src/ui/commands/helpCommand.ts b/packages/cli/src/ui/commands/helpCommand.ts
new file mode 100644
index 00000000..82d0d536
--- /dev/null
+++ b/packages/cli/src/ui/commands/helpCommand.ts
@@ -0,0 +1,20 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { OpenDialogActionReturn, SlashCommand } from './types.js';
+
+export const helpCommand: SlashCommand = {
+  name: 'help',
+  altName: '?',
+  description: 'for help on gemini-cli',
+  action: (_context, _args): OpenDialogActionReturn => {
+    console.debug('Opening help UI ...');
+    return {
+      type: 'dialog',
+      dialog: 'help',
+    };
+  },
+};
diff --git a/packages/cli/src/ui/commands/memoryCommand.test.ts b/packages/cli/src/ui/commands/memoryCommand.test.ts
new file mode 100644
index 00000000..47d098b1
--- /dev/null
+++ b/packages/cli/src/ui/commands/memoryCommand.test.ts
@@ -0,0 +1,249 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { vi, describe, it, expect, beforeEach, Mock } from 'vitest';
+import { memoryCommand } from './memoryCommand.js';
+import { type CommandContext, SlashCommand } from './types.js';
+import { createMockCommandContext } from '../../test-utils/mockCommandContext.js';
+import { MessageType } from '../types.js';
+import { getErrorMessage } from '@google/gemini-cli-core';
+
+vi.mock('@google/gemini-cli-core', async (importOriginal) => {
+  const original =
+    await importOriginal<typeof import('@google/gemini-cli-core')>();
+  return {
+    ...original,
+    getErrorMessage: vi.fn((error: unknown) => {
+      if (error instanceof Error) return error.message;
+      return String(error);
+    }),
+  };
+});
+
+describe('memoryCommand', () => {
+  let mockContext: CommandContext;
+
+  const getSubCommand = (name: 'show' | 'add' | 'refresh'): SlashCommand => {
+    const subCommand = memoryCommand.subCommands?.find(
+      (cmd) => cmd.name === name,
+    );
+    if (!subCommand) {
+      throw new Error(`/memory ${name} command not found.`);
+    }
+    return subCommand;
+  };
+
+  describe('/memory show', () => {
+    let showCommand: SlashCommand;
+    let mockGetUserMemory: Mock;
+    let mockGetGeminiMdFileCount: Mock;
+
+    beforeEach(() => {
+      showCommand = getSubCommand('show');
+
+      mockGetUserMemory = vi.fn();
+      mockGetGeminiMdFileCount = vi.fn();
+
+      mockContext = createMockCommandContext({
+        services: {
+          config: {
+            getUserMemory: mockGetUserMemory,
+            getGeminiMdFileCount: mockGetGeminiMdFileCount,
+          },
+        },
+      });
+    });
+
+    it('should display a message if memory is empty', async () => {
+      if (!showCommand.action) throw new Error('Command has no action');
+
+      mockGetUserMemory.mockReturnValue('');
+      mockGetGeminiMdFileCount.mockReturnValue(0);
+
+      await showCommand.action(mockContext, '');
+
+      expect(mockContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.INFO,
+          text: 'Memory is currently empty.',
+        },
+        expect.any(Number),
+      );
+    });
+
+    it('should display the memory content and file count if it exists', async () => {
+      if (!showCommand.action) throw new Error('Command has no action');
+
+      const memoryContent = 'This is a test memory.';
+
+      mockGetUserMemory.mockReturnValue(memoryContent);
+      mockGetGeminiMdFileCount.mockReturnValue(1);
+
+      await showCommand.action(mockContext, '');
+
+      expect(mockContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.INFO,
+          text: `Current memory content from 1 file(s):\n\n---\n${memoryContent}\n---`,
+        },
+        expect.any(Number),
+      );
+    });
+  });
+
+  describe('/memory add', () => {
+    let addCommand: SlashCommand;
+
+    beforeEach(() => {
+      addCommand = getSubCommand('add');
+      mockContext = createMockCommandContext();
+    });
+
+    it('should return an error message if no arguments are provided', () => {
+      if (!addCommand.action) throw new Error('Command has no action');
+
+      const result = addCommand.action(mockContext, '  ');
+      expect(result).toEqual({
+        type: 'message',
+        messageType: 'error',
+        content: 'Usage: /memory add <text to remember>',
+      });
+
+      expect(mockContext.ui.addItem).not.toHaveBeenCalled();
+    });
+
+    it('should return a tool action and add an info message when arguments are provided', () => {
+      if (!addCommand.action) throw new Error('Command has no action');
+
+      const fact = 'remember this';
+      const result = addCommand.action(mockContext, `  ${fact}  `);
+
+      expect(mockContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.INFO,
+          text: `Attempting to save to memory: "${fact}"`,
+        },
+        expect.any(Number),
+      );
+
+      expect(result).toEqual({
+        type: 'tool',
+        toolName: 'save_memory',
+        toolArgs: { fact },
+      });
+    });
+  });
+
+  describe('/memory refresh', () => {
+    let refreshCommand: SlashCommand;
+    let mockRefreshMemory: Mock;
+
+    beforeEach(() => {
+      refreshCommand = getSubCommand('refresh');
+      mockRefreshMemory = vi.fn();
+      mockContext = createMockCommandContext({
+        services: {
+          config: {
+            refreshMemory: mockRefreshMemory,
+            // eslint-disable-next-line @typescript-eslint/no-explicit-any
+          } as any,
+        },
+      });
+    });
+
+    it('should display success message when memory is refreshed with content', async () => {
+      if (!refreshCommand.action) throw new Error('Command has no action');
+
+      const refreshResult = {
+        memoryContent: 'new memory content',
+        fileCount: 2,
+      };
+      mockRefreshMemory.mockResolvedValue(refreshResult);
+
+      await refreshCommand.action(mockContext, '');
+
+      expect(mockContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.INFO,
+          text: 'Refreshing memory from source files...',
+        },
+        expect.any(Number),
+      );
+
+      expect(mockRefreshMemory).toHaveBeenCalledOnce();
+
+      expect(mockContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.INFO,
+          text: 'Memory refreshed successfully. Loaded 18 characters from 2 file(s).',
+        },
+        expect.any(Number),
+      );
+    });
+
+    it('should display success message when memory is refreshed with no content', async () => {
+      if (!refreshCommand.action) throw new Error('Command has no action');
+
+      const refreshResult = { memoryContent: '', fileCount: 0 };
+      mockRefreshMemory.mockResolvedValue(refreshResult);
+
+      await refreshCommand.action(mockContext, '');
+
+      expect(mockRefreshMemory).toHaveBeenCalledOnce();
+
+      expect(mockContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.INFO,
+          text: 'Memory refreshed successfully. No memory content found.',
+        },
+        expect.any(Number),
+      );
+    });
+
+    it('should display an error message if refreshing fails', async () => {
+      if (!refreshCommand.action) throw new Error('Command has no action');
+
+      const error = new Error('Failed to read memory files.');
+      mockRefreshMemory.mockRejectedValue(error);
+
+      await refreshCommand.action(mockContext, '');
+
+      expect(mockRefreshMemory).toHaveBeenCalledOnce();
+
+      expect(mockContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.ERROR,
+          text: `Error refreshing memory: ${error.message}`,
+        },
+        expect.any(Number),
+      );
+
+      expect(getErrorMessage).toHaveBeenCalledWith(error);
+    });
+
+    it('should not throw if config service is unavailable', async () => {
+      if (!refreshCommand.action) throw new Error('Command has no action');
+
+      const nullConfigContext = createMockCommandContext({
+        services: { config: null },
+      });
+
+      await expect(
+        refreshCommand.action(nullConfigContext, ''),
+      ).resolves.toBeUndefined();
+
+      expect(nullConfigContext.ui.addItem).toHaveBeenCalledWith(
+        {
+          type: MessageType.INFO,
+          text: 'Refreshing memory from source files...',
+        },
+        expect.any(Number),
+      );
+
+      expect(mockRefreshMemory).not.toHaveBeenCalled();
+    });
+  });
+});
diff --git a/packages/cli/src/ui/commands/memoryCommand.ts b/packages/cli/src/ui/commands/memoryCommand.ts
new file mode 100644
index 00000000..18ca96bb
--- /dev/null
+++ b/packages/cli/src/ui/commands/memoryCommand.ts
@@ -0,0 +1,106 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { getErrorMessage } from '@google/gemini-cli-core';
+import { MessageType } from '../types.js';
+import { SlashCommand, SlashCommandActionReturn } from './types.js';
+
+export const memoryCommand: SlashCommand = {
+  name: 'memory',
+  description: 'Commands for interacting with memory.',
+  subCommands: [
+    {
+      name: 'show',
+      description: 'Show the current memory contents.',
+      action: async (context) => {
+        const memoryContent = context.services.config?.getUserMemory() || '';
+        const fileCount = context.services.config?.getGeminiMdFileCount() || 0;
+
+        const messageContent =
+          memoryContent.length > 0
+            ? `Current memory content from ${fileCount} file(s):\n\n---\n${memoryContent}\n---`
+            : 'Memory is currently empty.';
+
+        context.ui.addItem(
+          {
+            type: MessageType.INFO,
+            text: messageContent,
+          },
+          Date.now(),
+        );
+      },
+    },
+    {
+      name: 'add',
+      description: 'Add content to the memory.',
+      action: (context, args): SlashCommandActionReturn | void => {
+        if (!args || args.trim() === '') {
+          return {
+            type: 'message',
+            messageType: 'error',
+            content: 'Usage: /memory add <text to remember>',
+          };
+        }
+
+        context.ui.addItem(
+          {
+            type: MessageType.INFO,
+            text: `Attempting to save to memory: "${args.trim()}"`,
+          },
+          Date.now(),
+        );
+
+        return {
+          type: 'tool',
+          toolName: 'save_memory',
+          toolArgs: { fact: args.trim() },
+        };
+      },
+    },
+    {
+      name: 'refresh',
+      description: 'Refresh the memory from the source.',
+      action: async (context) => {
+        context.ui.addItem(
+          {
+            type: MessageType.INFO,
+            text: 'Refreshing memory from source files...',
+          },
+          Date.now(),
+        );
+
+        try {
+          const result = await context.services.config?.refreshMemory();
+
+          if (result) {
+            const { memoryContent, fileCount } = result;
+            const successMessage =
+              memoryContent.length > 0
+                ? `Memory refreshed successfully. Loaded ${memoryContent.length} characters from ${fileCount} file(s).`
+                : 'Memory refreshed successfully. No memory content found.';
+
+            context.ui.addItem(
+              {
+                type: MessageType.INFO,
+                text: successMessage,
+              },
+              Date.now(),
+            );
+          }
+        } catch (error) {
+          const errorMessage = getErrorMessage(error);
+          context.ui.addItem(
+            {
+              type: MessageType.ERROR,
+              text: `Error refreshing memory: ${errorMessage}`,
+            },
+            Date.now(),
+          );
+        }
+      },
+    },
+  ],
+};
diff --git a/packages/cli/src/ui/commands/types.ts b/packages/cli/src/ui/commands/types.ts
new file mode 100644
index 00000000..09682d7a
--- /dev/null
+++ b/packages/cli/src/ui/commands/types.ts
@@ -0,0 +1,99 @@
+/**
+ * @license
+ * Copyright 2025 Google LLC
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+import { Config, GitService, Logger } from '@google/gemini-cli-core';
+import { LoadedSettings } from '../../config/settings.js';
+import { UseHistoryManagerReturn } from '../hooks/useHistoryManager.js';
+import { SessionStatsState } from '../contexts/SessionContext.js';
+
+// Grouped dependencies for clarity and easier mocking
+export interface CommandContext {
+  // Core services and configuration
+  services: {
+    // TODO(abhipatel12): Ensure that config is never null.
+    config: Config | null;
+    settings: LoadedSettings;
+    git: GitService | undefined;
+    logger: Logger;
+  };
+  // UI state and history management
+  ui: {
+    // TODO - As more commands are add some additions may be needed or reworked using this new context.
+    // Ex.
+    // history: HistoryItem[];
+    // pendingHistoryItems: HistoryItemWithoutId[];
+
+    /** Adds a new item to the history display. */
+    addItem: UseHistoryManagerReturn['addItem'];
+    /** Clears all history items and the console screen. */
+    clear: () => void;
+    /**
+     * Sets the transient debug message displayed in the application footer in debug mode.
+     */
+    setDebugMessage: (message: string) => void;
+  };
+  // Session-specific data
+  session: {
+    stats: SessionStatsState;
+  };
+}
+
+/**
+ * The return type for a command action that results in scheduling a tool call.
+ */
+export interface ToolActionReturn {
+  type: 'tool';
+  toolName: string;
+  toolArgs: Record<string, unknown>;
+}
+
+/**
+ * The return type for a command action that results in a simple message
+ * being displayed to the user.
+ */
+export interface MessageActionReturn {
+  type: 'message';
+  messageType: 'info' | 'error';
+  content: string;
+}
+
+/**
+ * The return type for a command action that needs to open a dialog.
+ */
+export interface OpenDialogActionReturn {
+  type: 'dialog';
+  // TODO: Add 'theme' | 'auth' | 'editor' | 'privacy' as migration happens.
+  dialog: 'help';
+}
+
+export type SlashCommandActionReturn =
+  | ToolActionReturn
+  | MessageActionReturn
+  | OpenDialogActionReturn;
+
+// The standardized contract for any command in the system.
+export interface SlashCommand {
+  name: string;
+  altName?: string;
+  description?: string;
+
+  // The action to run. Optional for parent commands that only group sub-commands.
+  action?: (
+    context: CommandContext,
+    args: string,
+  ) =>
+    | void
+    | SlashCommandActionReturn
+    | Promise<void | SlashCommandActionReturn>;
+
+  // Provides argument completion (e.g., completing a tag for `/chat resume <tag>`).
+  completion?: (
+    context: CommandContext,
+    partialArg: string,
+  ) => Promise<string[]>;
+
+  subCommands?: SlashCommand[];
+}