Microsoft Research Shows How PDD Kit Formally Verifies Agent-Written Web Apps
Formally verifying agent-written full-stack web apps with PDD Kit
- Who
- Microsoft Research
- What
- introduced PDD Kit, a toolkit that uses formal specifications and proofs to verify code written by coding agents
- Quote
PDD Kit is our toolkit for it.
What happened
Microsoft Research presents PDD Kit, a research prototype that turns reviewed intent into Verus specifications and checks agent-written Rust code against them, using tests for behavior outside the proof. In a roughly 5,000-line Pet Store app, the team formally verified the login logic and tested trusted components such as database lookups and password checking. PDD Kit currently verifies Rust, and the post describes its trusted assumptions and limits.
Why it matters
The Pet Store example shows how formal proofs and tests can cover different parts of an agent-written login flow, while making the assumptions outside the proof explicit.
Read next
See the full storyMicrosoft Research Introduces PDD Kit to Verify Agent-Written Rust CodeThe story so far
Microsoft Research introduced PDD Kit, a research prototype that checks agent-written Rust code against formal specifications; it currently verifies Rust because it uses Verus. The team used the kit on a roughly 5,000-line Pet Store app. It formally verified the login logic and used tests to check behavior outside the proof, including trusted components such as database lookups and password checking.
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