diff --git a/sidecars/reddit-post/tests/reddit-post.spec.js b/sidecars/reddit-post/tests/reddit-post.spec.js
new file mode 100644
index 0000000..bdd6677
--- /dev/null
+++ b/sidecars/reddit-post/tests/reddit-post.spec.js
@@ -0,0 +1,90 @@
+// @ts-check
+const { test, expect } = require('@playwright/test');
+const fs = require('fs');
+const path = require('path');
+
+const RESULT_PATH = path.join(__dirname, '..', 'test-results', 'result.json');
+
+function writeResult(result) {
+  fs.mkdirSync(path.dirname(RESULT_PATH), { recursive: true });
+  fs.writeFileSync(RESULT_PATH, JSON.stringify(result));
+}
+
+test.describe('reddit post', () => {
+  let outcome = { success: false, error: 'Test did not complete' };
+
+  test.afterEach(async () => {
+    writeResult(outcome);
+  });
+
+  test('logs into Reddit and creates a post', async ({ page }) => {
+    const username = process.env.REDDIT_USERNAME;
+    const password = process.env.REDDIT_PASSWORD;
+    const subreddit = process.env.SUBREDDIT;
+    const title = process.env.POST_TITLE;
+    const body = process.env.POST_BODY;
+
+    for (const [name, value] of Object.entries({
+      REDDIT_USERNAME: username,
+      REDDIT_PASSWORD: password,
+      SUBREDDIT: subreddit,
+      POST_TITLE: title,
+      POST_BODY: body,
+    })) {
+      if (!value) {
+        outcome = { success: false, error: `Missing required environment variable: ${name}` };
+        throw new Error(outcome.error);
+      }
+    }
+
+    try {
+      await page.goto('https://www.reddit.com/login/');
+
+      await page.fill('input[name="username"]', /** @type {string} */ (username));
+      await page.fill('input[name="password"]', /** @type {string} */ (password));
+      await page.click('button[type="submit"]');
+
+      try {
+        await expect(page.locator('span[name="avatar"], #USER_DROPDOWN_ID, [icon-name="account-circle-outline"]').first()).toBeVisible({ timeout: 20_000 });
+      } catch {
+        outcome = {
+          success: false,
+          error: 'Login did not complete — possible CAPTCHA, 2FA prompt, or invalid credentials',
+        };
+        throw new Error(outcome.error);
+      }
+
+      await page.goto(`https://www.reddit.com/r/${subreddit}/submit`);
+
+      const textTab = page.getByRole('button', { name: /^Text$/i }).first();
+      if (await textTab.isVisible({ timeout: 10_000 }).catch(() => false)) {
+        await textTab.click();
+      }
+
+      await page.getByPlaceholder(/title/i).first().fill(/** @type {string} */ (title));
+
+      const bodyField = page.locator('[data-testid="post-composer-rte"], div[role="textbox"]').first();
+      await bodyField.click();
+      await bodyField.fill(/** @type {string} */ (body));
+
+      const submitButton = page.getByRole('button', { name: /^Post$/i }).first();
+      await expect(submitButton).toBeEnabled({ timeout: 10_000 });
+      await submitButton.click();
+
+      try {
+        await page.waitForURL(/\/comments\//, { timeout: 20_000 });
+      } catch {
+        outcome = { success: false, error: 'Post submission did not complete — no redirect to the new post' };
+        throw new Error(outcome.error);
+      }
+
+      outcome = { success: true, url: page.url() };
+      expect(outcome.success).toBe(true);
+    } catch (err) {
+      if (outcome.success !== false || !outcome.error) {
+        outcome = { success: false, error: err instanceof Error ? err.message : String(err) };
+      }
+      throw err;
+    }
+  });
+});