Keep your Smartlook calls. Change two lines.

Keep session replay. Get a list of what to fix.

Sequential's own recorder starts on your page. It uses the same session id as your events. Each recording shows the console, network requests, errors and performance.

Then it gives you findings. A finding is a problem, the number of people who had it, and the sessions that show it.

Sequential counts each problem in all your sessions, not only the sessions that a person watched. It puts the problems that hit the most people first, with the evidence. It tells you what it counted. Your team decides what it means.

Your own agent can read these findings through MCP or the REST API. Your agent then works in your team's tools, for example it files the ticket. After you release the fix, your agent can ask again.

Change two lines

This works on the web. Sequential serves its own implementation of Smartlook's public smartlook() API. The calls in your code now continue to work.

1. 01

   Copy your key

   Each project has a Smartlook key that starts with sq_smartlook_. Setup shows it on the Smartlook tab. The key is public: it is in your page.

2. 02

   Change both lines

   Change the two marked lines in the snippet that you have now. If the script still loads from web-sdk.smartlook.com, Smartlook's recorder runs. Sequential then discards all data that it sends, also your events.

3. 03

   Check that it works

   Load a page in a normal browser. On Setup, a Smartlook line then shows, with a green dot and "receiving". The first event can take up to about a minute. Sequential refuses automated and headless browsers as bots.

c.src='https://api.usesequential.com/recorder.js';   // ← was web-sdk.smartlook.com
smartlook('init', 'sq_smartlook_…', {});   // ← your Sequential key; drop { region: … }

With npm, keep smartlook-client. Change the key and add one option, relayProxyUrl, set to the Sequential API address. Use the origin only, with no path. Do not set host.

import smartlook from 'smartlook-client';

smartlook.init('sq_smartlook_…', { relayProxyUrl: 'https://api.usesequential.com' });

Or give the work to your coding agent. On Setup, click Copy prompt. The prompt has your keys and tells the agent how to find your Smartlook install. Look at the change that the agent makes. Then check Setup.

What continues to work

Each Smartlook call becomes this in Sequential.

• track(name, props). A custom event, with your own event name.
• identify(userId, props). The user and their properties.
• navigation(path), page loads and route changes in your app. Page views.
• error(err) and uncaught errors. Errors.
• Clicks. A click, with the element and its text.

An example: one finding, one week

Illustrative example: Northlight Outfitters is a fictional shop.

The head of product opens one finding: a failed request on the shipping page. 38 people. In plain words, people get stuck at the shipping address. The postcode field refuses a space. Three sessions show it.

Her agent files WEB-231 in Jira with those sessions. Sequential does not connect to Jira. It finds, counts and answers.

One week after release 2026.10.09, she asks again. Measured after the release: 41% → 12% of sessions on the shipping page. This is a measurement, not a verdict. The team decides what to do next.

Good to know

• Mobile apps. Mobile apps need a different install. Sequential does not support Smartlook's mobile SDKs. For a mobile app, install PostHog's mobile SDK and point it at Sequential. This is more work than a two-line change.
• History. Your history does not move. Sequential does not import Smartlook recordings or events, and old Smartlook recordings do not play in Sequential. Before you switch, save the Smartlook data that you still need.
• Retention. The hosted preview keeps 7 days of data by default.
• Signed-in people. With the Smartlook script, one signed-in person counts as two users, and the replay player shows them as anonymous. The Sessions page and User detail still show the user id. The Sequential SDK links the two ids.
• Recording and masking. Set recording and masking in Settings, not in code. pause and disable stop your events, but not session replay. record({…}) does not change masking. Set both in Settings → Projects → Session replay before you go live. Sequential's servers apply these settings, so a page cannot capture more. Replay needs an active replay key on the project.
• Automatic capture. Some automatic capture does not come over. Sequential captures clicks, page views and errors automatically. It does not capture form, focus, input or network events as events. You still see those moments in the recording.
• Other features. Smartlook traffic does not give groups, feature flags, surveys, experiments or server-side SDKs. The support matrix has the full list.
• Relay. Set relayProxyUrl to the Sequential API address, not to a relay of your own.

Questions and answers