Expo iOS Development MCP Server

Instructions

Implementation Reference

• src/mcp/server.ts:339-358 (handler)

  MCP tool registration and handler for 'expo.logs.tail'. Calls getExpoLogsTail(args.lines) from expo module and returns formatted JSON response, with error handling.

  server.tool(
    "expo.logs.tail",
    "Get recent Expo/Metro logs",
    ExpoLogsTailInputSchema.shape,
    async (args) => {
      try {
        const logs = getExpoLogsTail(args.lines);
        return {
          content: [
            {
              type: "text",
              text: JSON.stringify(logs, null, 2),
            },
          ],
        };
      } catch (error) {
        return handleToolError(error);
      }
    }
  );

• src/mcp/schemas.ts:41-43 (schema)

  Zod input schema for the expo.logs.tail tool, defining optional 'lines' parameter defaulting to 100.

  export const ExpoLogsTailInputSchema = z.object({
    lines: z.number().optional().default(100).describe("Number of log lines to return."),
  });

• src/expo/expo.ts:227-229 (helper)

  Helper function getExpoLogsTail that wraps and delegates to getExpoLogs for retrieving Expo logs.

  export function getExpoLogsTail(lines: number = 100) {
    return getExpoLogs(lines);
  }

• src/expo/logs.ts:91-93 (helper)

  Core helper function getExpoLogs that retrieves the last N lines from the 'expo' logger category using logger.tail.

  export function getExpoLogs(lines: number = 100): LogEntry[] {
    return logger.tail("expo", lines);
  }