March 11 (Reuters) - OpenAI launched new tools for developers on Tuesday that will help them build advanced AI agents, using a few application programming interfaces (APIs), amid growing competition from Chinese AI startups.

AI agents are designed to independently execute complex real-world tasks without direct human intervention, while API is a strings of code which enables standardized communication, data exchange and functionality between software components.

The new tool, called the Responses API, is available to all developers at no additional cost. It replaces OpenAI's Assistants API, which is set to be phased out by the second half of 2026.

The development comes close on the heels of release of latest AI models by Chinese startups which claim to be on par or better than industry-leading models in the United States at a fraction of the cost.

Chinese startup Monica has grabbed attention over the past few days after its launched its autonomous AI agent Manus, weeks after DeepSeek was showered with praise by Silicon Valley executives and U.S. tech company engineers.

Monica, which claims that its Manus AI outperforms OpenAI's DeepResearch agent, said on Tuesday that it was partnering with the team behind Alibaba's Qwen AI models.

(Reporting by Akash Sriram and Rishi Kant in Bengaluru; Editing by Tasim Zahid)

((Akash.Sriram@thomsonreuters.com; On X as @HoodieOnVeshti; +91-99017-77617;))