feat: improve notification message clarity with MCP Tool Called label

- Update notification format to multi-line with explicit label
- First line: 'MCP Tool Called: tool_name'
- Second line: parameters (if enabled)
- Add comprehensive tests for notification formatting

Co-Authored-By: Claude <noreply@anthropic.com>

tests/notifications.test.ts

@@ -0,0 +1,141 @@
+import { App, Notice } from 'obsidian';
+import { NotificationManager } from '../src/ui/notifications';
+import { MCPPluginSettings } from '../src/types/settings-types';
+
+// Mock Notice constructor
+jest.mock('obsidian', () => {
+	const actualObsidian = jest.requireActual('obsidian');
+	return {
+		...actualObsidian,
+		Notice: jest.fn()
+	};
+});
+
+describe('NotificationManager', () => {
+	let app: App;
+	let settings: MCPPluginSettings;
+	let manager: NotificationManager;
+
+	beforeEach(() => {
+		jest.clearAllMocks();
+		app = {} as App;
+		settings = {
+			port: 3000,
+			autoStart: false,
+			apiKey: 'test-key',
+			notificationsEnabled: true,
+			showParameters: true,
+			notificationDuration: 3000,
+			logToConsole: false
+		};
+		manager = new NotificationManager(app, settings);
+	});
+
+	describe('showToolCall', () => {
+		it('should format message with MCP Tool Called label and newline when parameters shown', () => {
+			manager.showToolCall('read_note', { path: 'daily/2025-01-15.md' });
+
+			expect(Notice).toHaveBeenCalledWith(
+				expect.stringContaining('📖 MCP Tool Called: read_note\npath: "daily/2025-01-15.md"'),
+				3000
+			);
+		});
+
+		it('should format message without newline when parameters hidden', () => {
+			settings.showParameters = false;
+			manager = new NotificationManager(app, settings);
+
+			manager.showToolCall('read_note', { path: 'daily/2025-01-15.md' });
+
+			expect(Notice).toHaveBeenCalledWith(
+				'📖 MCP Tool Called: read_note',
+				3000
+			);
+		});
+
+		it('should format multiple parameters correctly', () => {
+			manager.showToolCall('search', {
+				query: 'test query',
+				folder: 'notes',
+				recursive: true
+			});
+
+			expect(Notice).toHaveBeenCalledWith(
+				expect.stringContaining('🔍 MCP Tool Called: search\nquery: "test query", folder: "notes", recursive: true'),
+				3000
+			);
+		});
+
+		it('should handle empty arguments object', () => {
+			manager.showToolCall('get_vault_info', {});
+
+			expect(Notice).toHaveBeenCalledWith(
+				'ℹ️ MCP Tool Called: get_vault_info',
+				3000
+			);
+		});
+
+		it('should handle null arguments', () => {
+			manager.showToolCall('get_vault_info', null);
+
+			expect(Notice).toHaveBeenCalledWith(
+				'ℹ️ MCP Tool Called: get_vault_info',
+				3000
+			);
+		});
+
+		it('should handle undefined arguments', () => {
+			manager.showToolCall('get_vault_info', undefined);
+
+			expect(Notice).toHaveBeenCalledWith(
+				'ℹ️ MCP Tool Called: get_vault_info',
+				3000
+			);
+		});
+
+		it('should use fallback icon for unknown tool', () => {
+			manager.showToolCall('unknown_tool', { path: 'test.md' });
+
+			expect(Notice).toHaveBeenCalledWith(
+				expect.stringContaining('🔧 MCP Tool Called: unknown_tool\npath: "test.md"'),
+				3000
+			);
+		});
+
+		it('should use JSON fallback for arguments with no known keys', () => {
+			manager.showToolCall('custom_tool', {
+				customKey: 'value',
+				anotherKey: 123
+			});
+
+			expect(Notice).toHaveBeenCalledWith(
+				'🔧 MCP Tool Called: custom_tool\n{"customKey":"value","anotherKey":123}',
+				3000
+			);
+		});
+
+		it('should truncate path when exceeds 30 characters', () => {
+			const longPath = 'very/long/path/to/my/notes/folder/file.md';
+			manager.showToolCall('read_note', { path: longPath });
+
+			expect(Notice).toHaveBeenCalledWith(
+				'📖 MCP Tool Called: read_note\npath: "very/long/path/to/my/notes/..."',
+				3000
+			);
+		});
+
+		it('should truncate JSON fallback when exceeds 50 characters', () => {
+			const longJson = {
+				veryLongKeyName: 'very long value that exceeds the character limit',
+				anotherKey: 'more data'
+			};
+			manager.showToolCall('custom_tool', longJson);
+
+			const call = (Notice as jest.Mock).mock.calls[0][0];
+			const lines = call.split('\n');
+			expect(lines[0]).toBe('🔧 MCP Tool Called: custom_tool');
+			expect(lines[1].length).toBeLessThanOrEqual(50);
+			expect(lines[1]).toMatch(/\.\.\.$/);
+		});
+	});
+});