> ## Documentation Index > Fetch the complete documentation index at: https://docs.devinenterprise.com/llms.txt > Use this file to discover all available pages before exploring further. # Testing & Video Recordings > How Devin tests your changes end-to-end and sends you video recordings as proof Devin can test your application end-to-end after creating a PR — running the app locally, interacting with it through the browser, and recording a video of the entire process. The recording is sent directly to you as an attachment so you can verify the changes work without pulling the branch yourself. ## How It Works After Devin creates a PR, it can enter **testing mode** — a structured workflow where Devin: 1. **Sets up the environment** — installs dependencies, starts services, logs into required accounts 2. **Plans the test** — reads the diff and codebase to create a minimal, focused test plan 3. **Records a video** — starts a screen recording, executes the test plan in the desktop, and annotates key moments 4. **Sends you the result** — stops the recording, processes the video, and sends it to you as a message attachment The goal is a short recording that a code reviewer watches and immediately thinks "yep, it works" — then merges the PR. ## Triggering a Test After creating a PR, Devin will offer to test the app for you. Click **Test the app** to have Devin start the testing workflow. Test the app button A setting to automatically run testing after PR creation — without needing to click the button — is coming soon. You can also ask Devin to test at any point during a session — for example, "test the changes you just made and send me a recording" or "verify the login page works and send me a video." ## The Testing Workflow When Devin enters testing mode, it follows a structured three-phase process: ### Phase 1: Setup Before any testing begins, Devin prepares the environment: * **Reads the PR and codebase** to understand what needs testing * **Checks for relevant skills** in the repo (under `.agents/skills/`) and follows them if found * **Logs into required services** and resolves access issues * **Checks available environments** (staging, dev, local) and verifies connectivity * **Requests missing secrets** from you if needed — Devin will ask for credentials up front and save them for future sessions Completing [environment configuration](/onboard-devin/environment) ahead of time makes testing much faster — Devin can skip installing dependencies, configuring services, and logging in at the start of each session. When Devin asks for credentials during testing, it saves them as [secrets](/product-guides/secrets) for future sessions so you only need to provide them once. ### Phase 2: Test planning Once setup is complete, Devin writes a short test plan: * Identifies the **single most important end-to-end flow** that proves the feature works * Writes concrete, unambiguous steps (e.g., "click the button labeled Save at the top right" — not "find the save option") * Grounds the plan in actual code — traces through the frontend to find the exact UI path to the feature * Only adds additional test flows if there's a genuinely critical edge case Devin sends you the plan as a short message before executing, so you can course-correct if needed. ### Phase 3: Recording and execution After CI is green and any review comments are addressed, Devin executes the test: 1. **Starts recording** — captures the full screen 2. **Annotates key moments** — adds text labels at important points (e.g., "Testing login flow", "Feature confirmed working") that appear in the final video 3. **Executes the test plan** — interacts with the app through the browser, following each step 4. **Stops recording** — the video is automatically processed with annotations and speed adjustments around key moments 5. **Sends the video** — attaches the recording to a message so you can watch it directly ## Video Recording Details Devin's screen recordings have several features that make them useful for review: * **Annotations** — Text labels appear at key moments in the video, marking what Devin is testing. The video slows down around annotated points so you can see the details. * **Auto-zoom** — The video automatically zooms into where Devin clicks and interacts, smoothly panning to follow the cursor and easing back out during idle moments. * **Automatic processing** — Raw recordings are processed to highlight important actions and compress idle time * **Sent as attachments** — Videos are attached to messages in your session, viewable directly in the Devin webapp or Slack Recordings are designed to be short and focused — a **quick sanity check** with one primary end-to-end flow that proves the feature works. If you need more exhaustive coverage, use your existing test suites and CI rather than visual recording. ## Skill Suggestions After testing your app, Devin writes down what it tried and what worked — setup steps, environment configuration, how to start the app — and proposes creating or updating a [Skill](/product-guides/skills) via PR. You can merge the PR as-is or tweak it to refine the instructions. Over time, this means Devin gets better at testing your project — each session's learnings build on the last. You can also prompt Devin to do this at any time (e.g., "create a skill for how to test this app"). See the [Skills guide](/product-guides/skills) for full details on creating and managing skills. Here's an example of a testing skill: ```markdown theme={null} --- name: test-before-pr description: Run the local dev server and verify pages before opening any PR that touches frontend code. --- ## Setup 1. Install dependencies: `npm install` 2. Start the database: `docker-compose up -d postgres` 3. Run migrations: `npx prisma migrate dev` 4. Start the dev server: `npm run dev` 5. Wait for "Ready on http://localhost:3000" ## Verify 1. Read the git diff to identify which pages changed 2. Open each affected page in the browser 3. Check for: console errors, layout issues, broken links 4. Screenshot each page at desktop (1280px) and mobile (375px) widths ## Before Opening the PR 1. Run `npm run lint` and fix any issues 2. Run `npm test` and confirm all tests pass 3. Include screenshots in the PR description ``` When writing or refining skills, be specific about what to verify: * "Test the checkout flow: add an item to cart, go to checkout, fill in the form, and verify the order confirmation page shows the correct total" * "Verify the dark mode toggle works on the settings page — text should be readable and no elements should disappear" * "Test that the CSV export downloads a file with the correct headers" * "Test everything" * "Make sure the app works" * "Check that nothing is broken" ## Troubleshooting ### Devin didn't offer to test Testing mode is available on sessions where Devin creates a PR with code changes. If Devin didn't offer, you can always ask directly: "Can you test these changes and record a video?" ### Recording failed If the recording fails to process, Devin will let you know. Common causes include the app crashing during testing or the video processing timing out. Devin can retry — just ask "Try recording again." Recording files are stored on Devin's machine, and Devin can send them to you at any time if you ask. ### Devin can't access the app If Devin can't reach your app during testing (e.g., login walls, VPN requirements), it will ask you for help. Provide credentials using [secrets](/product-guides/secrets), use the [Interactive Browser](/work-with-devin/devin-session-tools#interactive-browser) to complete authentication steps manually, or complete [environment configuration](/onboard-devin/environment) to pre-configure access so Devin doesn't run into these issues.