diff --git a/CHANGELOG/fix_e2e-realm-delete-flake.md b/CHANGELOG/fix_e2e-realm-delete-flake.md
new file mode 100644
index 0000000..7b2d82b
--- /dev/null
+++ b/CHANGELOG/fix_e2e-realm-delete-flake.md
@@ -0,0 +1,7 @@
+## Tests
+
+- The admin UI E2E test that deletes a realm now checks the realm cards instead of any text on the page, because the confirm modal and the success toast also show the realm name, so on a slow runner the page-wide match found several elements and failed at once with a strict-mode violation.
+
+## Docs
+
+- The admin UI E2E conventions now require scoped locators (card, row or cell) for assertions after a create, update or delete, and `admin-ui/CLAUDE.md` points agents to those conventions when they add E2E tests.
diff --git a/admin-ui/CLAUDE.md b/admin-ui/CLAUDE.md
index 1810947..7559fc2 100644
--- a/admin-ui/CLAUDE.md
+++ b/admin-ui/CLAUDE.md
@@ -47,7 +47,7 @@ tests/
 1. Write failing test (red) — include error/edge cases, not just happy path
 2. Implement minimal code (green)
 3. Refactor, re-run tests
-4. Add E2E test after unit tests pass
+4. Add E2E test after unit tests pass, following the conventions in `tests/e2e/README.md`
 
 ## Coding Rules
 
diff --git a/admin-ui/tests/e2e/README.md b/admin-ui/tests/e2e/README.md
index ecbd82d..97891d9 100644
--- a/admin-ui/tests/e2e/README.md
+++ b/admin-ui/tests/e2e/README.md
@@ -27,5 +27,9 @@ pnpm exec playwright test <spec-name>
 - Prefer role-based locators (`getByRole("cell" | "tab" | "button", ...)`). Use
   `exact: true` or an anchored regex when a substring would match multiple elements
   (e.g. a role name that is also a substring of its `role_id` cell).
+- After a create, update or delete, assert on the element that holds the data (`.ant-card`,
+  `getByRole("cell" | "row")`), not a page-wide `getByText(name)`: the confirm modal and the
+  success toast repeat the name, and several matches fail at once with a strict-mode
+  violation. Assert absence with `toHaveCount(0)` on that scoped locator.
 - Token self-service endpoints authenticate via the `X-Vault-Token` header, not the
   admin cookie — assert the header is present in their mocks.
diff --git a/admin-ui/tests/e2e/realms.spec.ts b/admin-ui/tests/e2e/realms.spec.ts
index 6129d5d..e7fc175 100644
--- a/admin-ui/tests/e2e/realms.spec.ts
+++ b/admin-ui/tests/e2e/realms.spec.ts
@@ -203,7 +203,8 @@ test.describe("Realms page", () => {
         await page.getByRole("button", { name: "Delete" }).last().click();
 
         // The realm must no longer appear in the cards.
-        await expect(page.getByText("my-service")).not.toBeVisible();
+        // Scope to `.ant-card`: the confirm modal and the success toast also show the realm name.
+        await expect(page.locator(".ant-card").filter({ hasText: "my-service" })).toHaveCount(0);
     });
 
     test("should create a SAML realm from pasted IdP metadata", async ({ page }) => {