
“Agents fail in ways that are hard to see,” Microsoft wrote in the blog post. “They drift from policy, produce unsafe outputs in edge cases, and behave differently in production than they did in testing. Generic benchmarks do not catch these failures because they are not built around your policies, your agent, or your use case.”
Rather than requiring developers to manually create evaluation suites, ASSERT translates written intent into reusable tests that can be integrated into AI development pipelines, the company said in the blog post.
With ASSERT, Microsoft is entering an increasingly competitive AI evaluation market that already includes platforms such as LangChain’s LangSmith, Braintrust, Patronus AI, Galileo, Arize AI’s Phoenix, and Promptfoo, which help enterprises benchmark, monitor, and validate large language model applications.
Behavioral testing remains immature
The release comes as enterprises rapidly expand AI agent deployments while formal evaluation practices remain the exception rather than the rule.

