e2e-tests-studio

claude mcp add playwright -- npx @playwright/mcp@latest

pnpm build:cli
cd packages/playground/e2e/kitchen-sink && pnpm dev

import { test, expect, Page } from '@playwright/test';
import { resetStorage } from '../__utils__/reset-storage';
import { selectFixture } from '../__utils__/select-fixture';
import { nanoid } from 'nanoid';
 
/**
 * FEATURE: [Name of feature]
 * USER STORY: As a user, I want to [action] so that [outcome]
 * BEHAVIOR UNDER TEST: [Specific behavior being validated]
 */
 
test.describe('[Feature Name] - Behavior Tests', () => {
  let page: Page;
 
  test.beforeEach(async ({ browser }) => {
    const context = await browser.newContext();
    page = await context.newPage();
  });
 
  test.afterEach(async () => {
    await resetStorage(page);
  });
 
  test.describe('when [the single precondition for these outcomes]', () => {
    test('[verb describing the single observable outcome]', async () => {
      // ARRANGE: Set up preconditions
      // - Navigate to the feature
      // - Configure any required state
      // ACT: Perform the user action that triggers the behavior
      // ASSERT: Verify the OUTCOME, not the UI state
      // - Check data persistence
      // - Verify downstream effects
      // - Confirm API calls made correctly
    });
  });
});

test.describe('when a different LLM provider is selected', () => {
  test('uses that provider for agent responses', async () => {
    // ARRANGE
    await page.goto('/agents/my-agent/chat');
 
    // Intercept API to verify provider
    let capturedProvider: string | null = null;
    await page.route('**/api/chat', route => {
      const body = JSON.parse(route.request().postData() || '{}');
      capturedProvider = body.provider;
      route.continue();
    });
 
    // ACT: Select a different provider
    await page.getByTestId('provider-selector').click();
    await page.getByRole('option', { name: 'OpenAI' }).click();
 
    // Send a message to trigger the agent
    await page.getByTestId('chat-input').fill('Hello');
    await page.getByTestId('send-button').click();
 
    // ASSERT: Verify the selected provider was used
    await expect.poll(() => capturedProvider).toBe('openai');
  });
});

test.describe('when a new agent is created', () => {
  test('persists after page reload', async () => {
    // ARRANGE
    await page.goto('/agents');
    const agentName = `Test Agent ${nanoid()}`;
 
    // ACT: Create new agent
    await page.getByTestId('create-agent-button').click();
    await page.getByTestId('agent-name-input').fill(agentName);
    await page.getByTestId('save-agent-button').click();
 
    // Wait for creation to complete
    await expect(page.getByText(agentName)).toBeVisible();
 
    // ASSERT: Verify persistence
    await page.reload();
    await expect(page.getByText(agentName)).toBeVisible({ timeout: 10000 });
  });
});

test.describe('when the weather tool is executed with a city', () => {
  test('returns formatted weather data for that city', async () => {
    // ARRANGE
    await selectFixture(page, 'weather-success');
    await page.goto('/tools/weather-tool');
 
    // ACT: Execute tool with parameters
    await page.getByTestId('param-city').fill('San Francisco');
    await page.getByTestId('execute-tool-button').click();
 
    // ASSERT: Verify OUTPUT content, not just that output appears
    const output = page.getByTestId('tool-output');
    await expect(output).toContainText('temperature');
    await expect(output).toContainText('San Francisco');
 
    // Verify structured data if applicable
    const outputText = await output.textContent();
    const outputData = JSON.parse(outputText || '{}');
    expect(outputData).toHaveProperty('temperature');
    expect(outputData).toHaveProperty('conditions');
  });
});

test.describe('when a multi-step workflow is run', () => {
  test('passes data between steps correctly', async () => {
    // ARRANGE
    await selectFixture(page, 'workflow-multi-step');
    const sessionId = nanoid();
    await page.goto(`/workflows/data-pipeline?session=${sessionId}`);
 
    // ACT: Trigger workflow execution
    await page.getByTestId('workflow-input').fill('test input data');
    await page.getByTestId('run-workflow-button').click();
 
    // ASSERT: Verify each step received correct input from previous step
    // Wait for completion
    await expect(page.getByTestId('workflow-status')).toHaveText('completed', { timeout: 30000 });
 
    // Check step outputs show data transformation chain
    const step1Output = await page.getByTestId('step-1-output').textContent();
    const step2Output = await page.getByTestId('step-2-output').textContent();
 
    // Verify step 2 received step 1's output as input
    expect(step2Output).toContain(step1Output);
  });
});

test.describe('when a multi-turn conversation is held', () => {
  test('maintains conversation context across messages', async () => {
    // ARRANGE
    await selectFixture(page, 'contextual-chat');
    const chatId = nanoid();
    await page.goto(`/agents/assistant/chat/${chatId}`);
 
    // ACT: Multi-turn conversation
    await page.getByTestId('chat-input').fill('My name is Alice');
    await page.getByTestId('send-button').click();
    await expect(page.getByTestId('assistant-message').last()).toBeVisible({ timeout: 20000 });
 
    await page.getByTestId('chat-input').fill('What is my name?');
    await page.getByTestId('send-button').click();
 
    // ASSERT: Verify context was maintained
    const response = page.getByTestId('assistant-message').last();
    await expect(response).toContainText('Alice', { timeout: 20000 });
  });
});

test.describe('when the API fails during tool execution', () => {
  test('shows an actionable error and allows a successful retry', async () => {
    // ARRANGE: Set up failure fixture
    await selectFixture(page, 'api-failure');
    await page.goto('/tools/flaky-tool');
 
    // ACT: Trigger the error
    await page.getByTestId('execute-tool-button').click();
 
    // ASSERT: Error is shown with recovery option
    await expect(page.getByTestId('error-message')).toContainText('failed');
    await expect(page.getByTestId('retry-button')).toBeVisible();
 
    // Switch to success fixture and retry
    await selectFixture(page, 'api-success');
    await page.getByTestId('retry-button').click();
 
    // Verify recovery worked
    await expect(page.getByTestId('tool-output')).toBeVisible({ timeout: 10000 });
    await expect(page.getByTestId('error-message')).not.toBeVisible();
  });
});

test('dropdown opens when clicked', async () => {
  await page.getByTestId('model-dropdown').click();
  await expect(page.getByRole('listbox')).toBeVisible();
});

test.describe('when a model is selected from the dropdown', () => {
  test('updates and persists the agent configuration', async () => {
    // Open dropdown and select model
    await page.getByTestId('model-dropdown').click();
    await page.getByRole('option', { name: 'GPT-4' }).click();
 
    // Verify the selection persists and affects behavior
    await page.reload();
    await expect(page.getByTestId('model-dropdown')).toHaveText('GPT-4');
 
    // Optionally: verify the model is used in actual requests
    // (via request interception or checking response metadata)
  });
});

<feature>-<scenario>.fixture.ts

Examples:
- agent-with-tools.fixture.ts
- chat-multi-turn-context.fixture.ts
- workflow-parallel-execution.fixture.ts
- tool-validation-error.fixture.ts
- mcp-server-timeout.fixture.ts

// fixtures/agent-provider-switch.fixture.ts
export const agentProviderSwitch = {
  name: 'agent-provider-switch',
  description: 'Tests that switching LLM providers changes agent behavior',
 
  // Mock responses for different providers
  responses: {
    openai: { content: 'Response from OpenAI', model: 'gpt-4' },
    anthropic: { content: 'Response from Anthropic', model: 'claude-3' },
  },
 
  expectedBehavior: {
    // When provider is switched, subsequent messages use new provider
    providerSwitchAffectsNextMessage: true,
    // Provider selection persists across page reload
    providerPersistsOnReload: true,
  },
};

cd packages/playground && pnpm test:e2e