Scenic MCP

Instructions

Implementation Reference

• src/tools.ts:300-370 (handler)

  The handler function that executes the 'send_keys' tool. It validates connection to Scenic app, checks input parameters, constructs a command with action 'send_keys', sends it to the Elixir backend via connection, parses response, and returns success/error messages.

  async function handleSendKeys(args: any) {
    try {
      const isRunning = await conn.checkTCPServer();
      if (!isRunning) {
        return {
          content: [
            {
              type: 'text',
              text: 'Cannot send keys: No Scenic application connected.\n\nUse connect_scenic first or start your Scenic application. The MCP server will automatically detect when the app becomes available.',
            },
          ],
          isError: false,
        };
      }
  
      const { text, key, modifiers } = args;
  
      if (!text && !key) {
        return {
          content: [
            {
              type: 'text',
              text: 'Error: Must provide either "text" or "key" parameter',
            },
          ],
          isError: true,
        };
      }
  
      const command = {
        action: 'send_keys',
        text,
        key,
        modifiers: modifiers || [],
      };
  
      const response = await conn.sendToElixir(command);
      const data = JSON.parse(response);
  
      if (data.error) {
        return {
          content: [
            {
              type: 'text',
              text: `Error sending keys: ${data.error}`,
            },
          ],
          isError: true,
        };
      }
  
      return {
        content: [
          {
            type: 'text',
            text: `Keys sent successfully!\n${JSON.stringify(data, null, 2)}`,
          },
        ],
      };
    } catch (error) {
      return {
        content: [
          {
            type: 'text',
            text: `Error sending keys: ${error instanceof Error ? error.message : 'Unknown error'}`,
          },
        ],
        isError: true,
      };
    }
  }

• src/tools.ts:46-70 (schema)

  Tool schema definition including name, description, and inputSchema specifying parameters for text, key, and modifiers with types and descriptions.

  {
    name: 'send_keys',
    description: 'KEYBOARD INPUT: Send text input or special keystrokes to the Scenic application. Use for typing text, navigation shortcuts, testing keyboard interactions. Supports text, special keys (enter, escape, tab), and modifier combinations (ctrl+c, cmd+s).',
    inputSchema: {
      type: 'object',
      properties: {
        text: {
          type: 'string',
          description: 'Text to type (each character will be sent as individual key presses)',
        },
        key: {
          type: 'string',
          description: 'Special key name (e.g., enter, escape, tab, backspace, delete, up, down, left, right, home, end, page_up, page_down, f1-f12)',
        },
        modifiers: {
          type: 'array',
          items: {
            type: 'string',
            enum: ['ctrl', 'shift', 'alt', 'cmd', 'meta'],
          },
          description: 'Modifier keys to hold while pressing the key',
        },
      },
    },
  },

• src/tools.ts:194-195 (registration)

  Registration in the tool handler router (handleToolCall switch statement) that dispatches 'send_keys' calls to the handleSendKeys function.

  case 'send_keys':
    return await handleSendKeys(args);