diff --git a/.claude/skills/qa/SKILL.md b/.claude/skills/qa/SKILL.md
index ba54d16..679770f 100644
--- a/.claude/skills/qa/SKILL.md
+++ b/.claude/skills/qa/SKILL.md
@@ -65,7 +65,7 @@ npm run test:e2e          # Playwright: E2E tests from previous QA runs
 Note any failures — these are regressions and must be treated as High bugs.
 
 ### 6. Write Unit Tests
-Before E2E tests, identify and test isolated logic with Vitest in `src/__tests__/PROJ-X-*.test.ts`:
+Before E2E tests, identify and test isolated logic with Vitest. Place tests **co-located** next to the source file (e.g. `src/hooks/useFeature.test.ts` next to `src/hooks/useFeature.ts`):
 
 **What to unit test (evaluate each):**
 - Custom hooks with non-trivial logic (e.g. `useKanbanStorage`: localStorage read/write, error fallback)
diff --git a/CLAUDE.md b/CLAUDE.md
index a241491..ceb6c68 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -47,14 +47,18 @@ All features tracked in `features/INDEX.md`. Every skill reads it at start and u
 - **Single Responsibility:** One feature per spec file
 - **shadcn/ui first:** NEVER create custom versions of installed shadcn components
 - **Human-in-the-loop:** All workflows have user approval checkpoints
+- **Tests:** Unit tests co-located next to source files (`useHook.test.ts` next to `useHook.ts`). E2E tests in `tests/`.
 
 ## Build & Test Commands
 
 ```bash
-npm run dev        # Development server (localhost:3000)
-npm run build      # Production build
-npm run lint       # ESLint
-npm run start      # Production server
+npm run dev          # Development server (localhost:3000)
+npm run build        # Production build
+npm run lint         # ESLint
+npm run start        # Production server
+npm test             # Vitest unit/integration tests
+npm run test:e2e     # Playwright E2E tests
+npm run test:all     # Both test suites
 ```
 
 ## Product Context