Expo MCP Server

Instructions

Implementation Reference

• src/file.ts:10-31 (handler)

  The readFile tool handler function that reads and returns the content of the specified file.

  export async function readFile(args: { filePath: string }, { log }: LogContext) {
    try {
      log.info(`Reading file at path: ${args.filePath}`);
  
      const normalizedPath = path.normalize(args.filePath);
      const fileContent = await fs.promises.readFile(normalizedPath, "utf8");
  
      log.info(`Successfully read file: ${normalizedPath}`);
  
      return {
        content: [
          {
            type: "text",
            text: fileContent,
          },
        ],
      };
    } catch (error: any) {
      log.error(`Error reading file: ${error.message}`);
      throw new Error(`Failed to read file: ${error.message}`);
    }
  }

• src/index.ts:18-25 (registration)

  Registration of the readFile tool on the MCP server, including schema definition and handler reference.

  addTool({
    name: "readFile",
    description: "Read the contents of a file",
    parameters: z.object({
      filePath: z.string().describe("The path to the file to read"),
    }),
    execute: readFile,
  });