capture_screenshot

Capture screenshots from Android devices during testing and save them to designated test folders for documentation and debugging purposes.

Instructions

Capture a screenshot and save it to the test folder

Input Schema

TableJSON Schema

Name	Required	Description	Default
`test_name`	Yes	Name of the test folder where to save the screenshot
`step_name`	Yes	Name of the step for the screenshot file (e.g., "001_login")

Implementation Reference

src/tools/handlers.ts:97-129 (handler)

The main handler function that implements the capture_screenshot tool logic. Uses ADB screencap to capture and save the screenshot, then returns it as base64-encoded image.

capture_screenshot: async (args: any) => {
  const { test_name, step_name } = args as { 
    test_name: string; 
    step_name: string; 
  };
  
  const testPath = path.join(getBaseTestPath(), test_name);
  const screenshotPath = path.join(testPath, `${step_name}_step.png`);
  
  if (!fs.existsSync(testPath)) {
    fs.mkdirSync(testPath, { recursive: true });
  }
  
  await executeCommand(`adb exec-out screencap -p > "${screenshotPath}"`);
  
  // Read the screenshot file and convert to base64
  const imageData = fs.readFileSync(screenshotPath);
  const base64Image = imageData.toString('base64');
  
  return {
    content: [
      {
        type: 'text',
        text: `Screenshot captured: ${screenshotPath}`,
      },
      {
        type: 'image',
        data: base64Image,
        mimeType: 'image/png',
      },
    ],
  };
},

src/tools/definitions.ts:44-61 (schema)

The schema definition for the capture_screenshot tool, including input parameters test_name and step_name.

{
  name: 'capture_screenshot',
  description: 'Capture a screenshot and save it to the test folder',
  inputSchema: {
    type: 'object',
    properties: {
      test_name: {
        type: 'string',
        description: 'Name of the test folder where to save the screenshot',
      },
      step_name: {
        type: 'string',
        description: 'Name of the step for the screenshot file (e.g., "001_login")',
      },
    },
    required: ['test_name', 'step_name'],
  },
},

src/index.ts:32-46 (registration)

Registration of tool handlers via MCP server's CallToolRequestSchema. Looks up handler from toolHandlers object by tool name.

server.setRequestHandler(CallToolRequestSchema, async (request) => {
  const { name, arguments: args } = request.params;

  try {
    const handler = toolHandlers[name as keyof typeof toolHandlers];
    if (!handler) {
      throw new McpError(ErrorCode.MethodNotFound, `Unknown tool: ${name}`);
    }

    return await handler(args);
  } catch (error) {
    const errorMessage = error instanceof Error ? error.message : String(error);
    throw new McpError(ErrorCode.InternalError, `Tool execution failed: ${errorMessage}`);
  }
});

src/index.ts:26-30 (registration)
Registration of tool schemas via MCP server's ListToolsRequestSchema. Returns the toolDefinitions array containing the schema for capture_screenshot.
```
server.setRequestHandler(ListToolsRequestSchema, async () => {
  return {
    tools: toolDefinitions,
  };
});
```

Android Debug Bridge MCP