OpenAI announced Monday its acquisition of Promptfoo, an AI security startup founded in 2024 to safeguard large language models (LLMs) from online threats.
The leading AI research company stated in a blog post that, upon the deal’s finalization, Promptfoo’s technology will be integrated into OpenAI Frontier, its enterprise platform for AI agents.
While the development of independent AI agents performing digital tasks has generated excitement about productivity gains, it has also provided malicious actors with new opportunities to access sensitive data or manipulate automated systems. This acquisition highlights how frontier labs are striving to ensure their technology can be deployed safely in critical business operations.
Promptfoo was established by Ian Webster and Michael D’Angelo to develop tools companies can utilize to test security vulnerabilities in LLMs, including an open-source interface and library. The company reports that its products are employed by over 25% of Fortune 500 companies.
Promptfoo has raised only $23 million since its founding and was valued at $86 million after its most recent round in July 2025, according to Pitchbook. OpenAI did not disclose the financial terms of the transaction.
OpenAI’s post indicated that Promptfoo’s technology will enable its agent platform to perform automated red-teaming, evaluate agentic workflows for security concerns, and monitor activities for risks and compliance needs. The company also stated its intention to continue expanding Promptfoo’s open-source offering.