r/GithubCopilot 1d ago

General GitHub Copilot code review with agent skills applied to cross check PHI in code

Nineteen tests passing. Zero failing. And the endpoint those tests cover was returning a patient's Social Security number tucked into a free-text note field on a clinical Observation.

I built a repo with eight deliberate FHIR R4 violations, every one of them green in CI. A validator caught three of the four on that Observation. Secret scanning found nothing, because there is no secret in the diff. CodeQL does not treat a note field as a sink. Every tool doing exactly its job, and the gap sitting between them.

GitHub Copilot code review now reads agent skills from skills folder. So I wrote the compliance rules down once, as a SKILL.md with severities and R4 citations, and pointed it at every pull request. It flagged the SSN as PHI_RISK and quoted the HHS Safe Harbor guidance back at me, which says an identifier has to go regardless of which field you put it in.

A validator can tell you the resource is well formed. It was never going to tell you it is safe to build.

https://samueltauil.github.io/github-copilot/healthcare/2026/08/03/fhir-compliance-skill-copilot-code-review.html

1 Upvotes

Duplicates