Android UI Assist MCP Server

import { z } from 'zod'; // Device information interfaces export interface AndroidDevice { id: string; status: 'device' | 'offline' | 'unauthorized' | 'unknown'; model?: string; product?: string; transportId?: string; usb?: string; productString?: string; } // Screenshot response interfaces export interface ScreenshotResponse { data: string; // Base64 encoded image data format: 'png'; width: number; height: number; deviceId: string; timestamp: number; } // Error handling interfaces export interface ADBError { code: string; message: string; details?: any; suggestion?: string; } export class ADBCommandError extends Error implements ADBError { code: string; details?: any; suggestion?: string; constructor(code: string, message: string, details?: any, suggestion?: string) { super(message); this.name = 'ADBCommandError'; this.code = code; this.details = details; this.suggestion = suggestion; } } export class ADBNotFoundError extends ADBCommandError { constructor() { super( 'ADB_NOT_FOUND', 'Android Debug Bridge (ADB) not found', null, 'Please install Android SDK Platform Tools and ensure ADB is in your PATH' ); this.name = 'ADBNotFoundError'; } } export class DeviceNotFoundError extends ADBCommandError { constructor(deviceId: string) { super( 'DEVICE_NOT_FOUND', `Device with ID '${deviceId}' not found`, { deviceId }, 'Please check if the device is connected and authorized' ); this.name = 'DeviceNotFoundError'; } } export class NoDevicesFoundError extends ADBCommandError { constructor() { super( 'NO_DEVICES_FOUND', 'No Android devices found', null, 'Please connect an Android device or start an emulator and ensure USB debugging is enabled' ); this.name = 'NoDevicesFoundError'; } } export class ScreenshotCaptureError extends ADBCommandError { constructor(deviceId: string, originalError?: Error) { super( 'SCREENSHOT_CAPTURE_FAILED', `Failed to capture screenshot from device '${deviceId}'`, { deviceId, originalError: originalError?.message }, 'Please ensure the device is connected and screen is unlocked' ); this.name = 'ScreenshotCaptureError'; } } // Tool input schemas export const TakeScreenshotInputSchema = z.object({ deviceId: z .string() .optional() .describe( 'The ID of the Android device to capture a screenshot from. If not provided, uses the first available device.' ), format: z .enum(['png']) .default('png') .describe('The image format for the screenshot. Currently only PNG is supported.'), }); export const ListDevicesInputSchema = z.object({}); // Tool output schemas export const TakeScreenshotOutputSchema = z.object({ data: z.string().describe('Base64 encoded image data'), format: z.string().describe('Image format (png)'), width: z.number().describe('Image width in pixels'), height: z.number().describe('Image height in pixels'), deviceId: z.string().describe('ID of the device the screenshot was taken from'), timestamp: z.number().describe('Unix timestamp when the screenshot was captured'), }); export const ListDevicesOutputSchema = z.object({ devices: z .array( z.object({ id: z.string().describe('Device ID'), status: z.string().describe('Device status'), model: z.string().optional().describe('Device model'), product: z.string().optional().describe('Product name'), transportId: z.string().optional().describe('Transport ID'), usb: z.string().optional().describe('USB information'), productString: z.string().optional().describe('Product string'), }) ) .describe('List of connected Android devices'), }); // MCP Tool schemas export const TakeScreenshotToolSchema = { type: 'object' as const, properties: { deviceId: { type: 'string' as const, description: 'The ID of the Android device to capture a screenshot from. If not provided, uses the first available device.', }, format: { type: 'string' as const, enum: ['png'], default: 'png', description: 'The image format for the screenshot. Currently only PNG is supported.', }, }, required: [] as string[], }; export const ListDevicesToolSchema = { type: 'object' as const, properties: {}, required: [] as string[], }; // Type exports export type TakeScreenshotInput = z.infer<typeof TakeScreenshotInputSchema>; export type ListDevicesInput = z.infer<typeof ListDevicesInputSchema>; export type TakeScreenshotOutput = z.infer<typeof TakeScreenshotOutputSchema>; export type ListDevicesOutput = z.infer<typeof ListDevicesOutputSchema>;