Analyze React component source code to understand UI structure, then generate idiomatic Cypress E2E tests following Metabase conventions. Falls back to Playwright MCP browser exploration only when code reading and screenshot debugging are insufficient.
You are writing Cypress E2E tests for the Metabase codebase. Before generating ANY test code, you MUST analyze React component source code to understand DOM structure, selectors, and user flows.
e2e/support/helpers/ — all shared helpers (restore, signInAs, openOrdersTable, etc.)e2e/support/cypress_sample_database.ts — table/field schema constants (ORDERS, PRODUCTS, etc.)e2e/support/cypress_sample_instance_data.ts — instance-specific IDs (ORDERS_DASHBOARD_ID, NORMAL_USER_ID, etc.)e2e/test/scenarios/ to find the closest existing spec to the area under test.
Study its patterns — match them exactly.frontend/src/metabase/ to find React components for the feature area.Read React component source to understand DOM structure. No browser needed — source code has everything.
frontend/src/metabase/ for the feature area.data-testid in relevant components.aria-label in relevant components.Api.use, fetch, useQuery, endpoint definitions to identify API calls to intercept.cy.intercept patterns.Use MB_EDITION=oss by default. Only use MB_EDITION=ee when the user explicitly asks to write an enterprise test.
Start the backend using run_in_background: true (NOT &).
bin/e2e-backend automatically detects if a backend is already running and reuses it.
MB_EDITION=oss bin/e2e-backend
Do NOT manually generate snapshots by running unrelated test specs.
The bun test-cypress runner has GENERATE_SNAPSHOTS: true by default and automatically
generates snapshots before running any spec. When running tests in Phase 4 via the /e2e-test skill,
snapshots will be generated on the first run if they don't already exist.
Restore clean test data:
curl -sf -X POST http://localhost:4000/api/testing/restore/default
Place specs in e2e/test/scenarios/<area>/ mirroring the URL structure.
Name: <feature>.cy.spec.js (NOT .cy.spec.ts).
cy.H: All helpers are accessed via const { H } = cy; — NOT via direct imports from e2e/support/helpers.const { H } = cy;
describe("feature name", () => {
beforeEach(() => {
H.restore();
cy.signInAsAdmin();
});
});
cypress_sample_database.import { ORDERS, ORDERS_ID, PRODUCTS } from "e2e/support/cypress_sample_database";
cypress_sample_instance_data.import { ORDERS_DASHBOARD_ID } from "e2e/support/cypress_sample_instance_data";
Selectors (priority order):
cy.findByText() / cy.findByLabelText() / cy.findByRole() — from @testing-library/cypresscy.findByTestId() — for data-testid attributescy.get("[data-testid='...']") — fallbackNavigation helpers: Use existing helpers like H.openOrdersTable(), H.openNativeEditor(),
H.visitDashboard(id), H.visitQuestion(id) instead of raw cy.visit() chains.
Grep e2e/support/helpers/ to discover what's available for your area.
API setup over UI setup: Use cy.request() or existing API helpers to set up state.
Only use the UI for the flow you're actually testing.
Assertions: Assert on visible text, URL, aria state — not DOM structure.
Waits: Never use cy.wait(ms). Use cy.intercept() + cy.wait("@alias") for API calls,
or cy.findByText().should("be.visible") for DOM readiness.
Isolation: Each it() block must be independently runnable.
Don't depend on state from a previous it().
const { H } = cy;
import { ORDERS_DASHBOARD_ID } from "e2e/support/cypress_sample_instance_data";
import { ORDERS, ORDERS_ID } from "e2e/support/cypress_sample_database";
describe("area > sub-area > feature (#issue-number)", () => {
beforeEach(() => {
H.restore();
cy.signInAsAdmin();
});
it("should do the primary happy-path thing", () => {
// test
});
it("should handle the edge case", () => {
// test
});
});
When you identified API calls during code analysis, stub or wait on them:
cy.intercept("POST", "/api/dataset").as("dataset");
// ... trigger action ...
cy.wait("@dataset");
After generating specs:
e2e/support/helpers/)./e2e-test skill to run tests — do NOT run bun test-cypress directly.
The /e2e-test skill handles edition selection, snapshot management, and correct env vars.
/e2e-test GREP="should do the thing" --spec e2e/test/scenarios/<path>
If you created multiple it() blocks, run each one individually to isolate failures.When a test fails, try to fix it from Cypress output first:
(Screenshots)).If you cannot diagnose the issue after 2 attempts, proceed to Phase 6.
Only reach this phase after 2 failed fix attempts from Phase 5. The backend is already running.
Restore clean test data:
curl -sf -X POST http://localhost:4000/api/testing/restore/default
Bypass CSP headers before navigating (Metabase serves strict CSP that blocks dev server scripts).
Use browser_run_code to set this up:
async (page) => {
// Strip CSP headers so the page loads (mirrors Cypress chromeWebSecurity: false)
await page.context().route('**/*', async (route) => {
const response = await route.fetch();
const headers = { ...response.headers() };
delete headers['content-security-policy'];
delete headers['content-security-policy-report-only'];
await route.fulfill({ response, headers });
});
// Sign in via API
const response = await page.request.post('http://localhost:4000/api/session', {
data: { username: '[email protected]', password: '12341234' }
});
const session = await response.json();
await page.context().addCookies([{
name: 'metabase.DEVICE',
value: session.id,
domain: 'localhost',
path: '/'
}]);
await page.goto('http://localhost:4000');
await page.waitForLoadState('networkidle');
return 'signed in';
}
Maintain an observation log incrementally. After EVERY significant Playwright interaction, IMMEDIATELY append what you observed to the scratch file BEFORE performing the next interaction:
cat >> /tmp/e2e-observations.md << 'OBSERVATION'
## [Page/Flow name]
- URL: /question/notebook#...
- Clicked: "Box plot" button → visible text "Box plot", role: radio
- Selectors: data-testid="viz-type-button", findByText("Box plot")
- API call: POST /api/dataset (triggered on viz change)
- Key state: after selecting viz type, summary sidebar shows metric picker
OBSERVATION
For each page/flow:
browser_snapshot).data-testid attrs, API calls.After exploration:
cat /tmp/e2e-observations.mdrm -f /tmp/e2e-observations.mdAfter all tests pass (or after giving up on fixing failures), always kill the backend on port 4000:
lsof -ti:4000 | xargs kill 2>/dev/null || true
Do NOT use broad pkill patterns — there may be other Metabase instances on different ports.
The backend process started in Phase 2 will NOT be killed automatically when the Claude session ends.
Leaving it running wastes resources and can interfere with future sessions. Always clean up.
cypress_sample_database or cypress_sample_instance_data.cy.wait(1000) or any numeric wait.cypress/e2e/ — Metabase uses e2e/test/scenarios/.e2e/support/helpers — use const { H } = cy;.