Some brokers don't allow traders to use robots for different practical and regulatory reasons. Generally, however, most established, reputable brokers will allow traders to use robots or EAs responsibly. There is more to automated trading than just your trading.

What are Stock Trading Bots for TD Ameritrade? Stock trading bots allow stock traders to buy, sell, and trade stocks and other securities automatically using a bot that executes trades automatically based on a specific trading strategy, with the goal of automating profits.