ai(rules[AGENTS]): add functional-only test style guideline

tony · tony · commit 24bec22b5f9c · 2026-01-10T11:50:12.000-06:00
diff --git a/AGENTS.md b/AGENTS.md
@@ -188,6 +188,8 @@ PosixPath('.../repo')
 
 ### Testing
 
+**Use functional tests only**: Write tests as standalone functions (`test_*`), not classes. Avoid `class TestFoo:` groupings - use descriptive function names and file organization instead. This applies to pytest tests, not doctests.
+
 #### Using libvcs Fixtures
 
 When writing tests, leverage libvcs's pytest plugin fixtures:
