Seatext library / BotRefund evidence
How to Implement BotRefund's Playwright Init Scripts for Better Detection Accuracy
Add BotRefund's detection script to your site, let it collect browser-level signals alongside your existing setup, and verify the results against real traffic. The init script is one of 106 independent checks BotRefund uses,...
✓ Built for advertisers who need clear, refund-ready traffic evidence.
To implement BotRefund's Playwright Init Scripts check, you add the BotRefund detection snippet to your website so it can collect browser-level evidence on each visit. That evidence then feeds into BotRefund's prediction AI alongside the other independent checks, and the combined pattern determines whether a visit is flagged as bot or human. You do not tune the init script in isolation; you deploy it, let it run, and verify that the signals it produces are reaching your BotRefund dashboard.
The Playwright Init Scripts check works by looking for mismatches that automated browsers create when they patch or hide standard browser APIs. A normal browser runs those APIs as designed, so its properties stay consistent. An automated browser often alters them, and those alterations can break when inspected from a different angle. BotRefund treats that mismatch as one piece of evidence, not a verdict, and cross-checks it against network, device, and behavioral data.
Prerequisites Before You Start
You need a BotRefund account and access to the website where you will install the detection script. You should also have a way to test with both real and automated traffic so you can confirm the check is producing useful signals. If you run paid campaigns on Google or Meta, keep your click identifiers (like GCLIDs) intact before making changes, so BotRefund can associate suspicious sessions with the right campaign data.
Step 1: Add the Init Script to Your Site
Place the BotRefund detection script in the <head> of your pages, or use a tag manager to inject it. The script needs to load early in the page lifecycle so it can capture browser properties before any automation tools have a chance to patch them. If the script loads too late, a bot may have already hidden its traces by the time the check runs.
Confirm that the script fires on every page a visitor can land on, not just your homepage. Bots often enter through deep links or ad landing pages, so coverage gaps will leave blind spots in your detection data.
Step 2: Confirm Signal Collection
After the script is live, open your BotRefund dashboard and check that visits are appearing with signal data attached. You should see the Playwright Init Scripts signal contributing to session records. If sessions show up but the init-script signal is missing, the script may not be loading correctly or may be blocked by another tag.
Use your browser's developer tools to verify the script is present in the page source and executing without errors. Check for network requests to BotRefund endpoints to confirm data is being sent.
Step 3: Let the Corroboration System Work
BotRefund does not flag a visit as a bot based on the init-script signal alone. The signal goes into the prediction AI, which weighs it against browser, network, device, and behavioral evidence. Your job at this stage is to let enough traffic flow through the system so the AI has a meaningful pattern to evaluate.
A single anomaly is not a bot verdict. Privacy tools, corporate networks, and unusual devices can all produce unexpected browser behavior for genuine visitors. BotRefund keeps each signal as evidence and cross-checks it against the rest of the session data.
Step 4: Review Session-Level Explanations
Each finding BotRefund produces includes a session-by-session explanation rather than a generic invalid-traffic estimate. When you review flagged visits, look at how the init-script signal fits with the other signals in that session. A visit flagged as bot should show a cluster of supporting evidence, not just one browser tell.
This review step matters because it helps you distinguish real bot traffic from edge-case human visitors. If you see visits flagged solely on the init-script signal with no corroboration, treat those with caution and investigate further before acting.
Step 5: Test With Real and Automated Traffic
Send a mix of real human visits and known automated visits through your site. For real traffic, browse naturally with pauses, scrolling, and varied navigation. For automated traffic, run a Playwright or similar browser-automation script that loads pages without human-like interaction.
Check whether BotRefund correctly separates the two. The automated visits should show the init-script mismatch signal along with other supporting signals like absence of scrolling, superhuman input speed, or unnatural session durations. The real visits should not trigger a bot flag.
Step 6: Connect Campaign Data for Refund Reports
If your goal is to recover ad spend from Google or Meta, make sure BotRefund can associate each flagged session with the right campaign, click ID, placement, and timestamp. This means preserving your attribution parameters before you pause or change any campaigns. BotRefund turns each finding into a refund-ready report with click IDs, campaign details, timestamps, session recordings, and signal-by-signal reasoning.
The report format matters because Google and Meta platform teams need structured evidence to review invalid traffic claims. A security log is not enough; the data needs to be in a format their reviewers can act on.
Common Mistake: Treating One Signal as a Verdict
The most frequent implementation error is acting on the init-script signal in isolation. If you block or exclude visits based on a single browser mismatch, you risk filtering out real people who use privacy tools, VPNs, corporate networks, or unusual devices. BotRefund's accuracy comes from corroboration across multiple independent checks, not from any one rule. Always wait for the full pattern before making decisions.
How to Verify Your Implementation
Run a controlled test over 24 to 48 hours. Compare the visits BotRefund flags as bots against your own server logs or analytics. Look for consistency: flagged visits should show technical and behavioral patterns that align with automation, such as no scrolling, uniform click paths, or superhuman input speeds. If the flags line up with what you see in your own data, the implementation is working. If they do not, revisit the script placement and signal collection steps.
What the Playwright Init Scripts Check Actually Detects
The check targets a specific class of evasion: automation tools that patch or override browser APIs to hide their presence. When a tool like Playwright or Puppeteer modifies properties such as navigator.webdriver, window.chrome, or permission APIs, those modifications can create inconsistencies that a real browser session would not produce. BotRefund inspects the browser from multiple angles to find those inconsistencies.
This is one of 106 independent checks BotRefund uses. Other checks in the same category include the Clean Context Iframe check, which also looks for API mismatches from a different inspection point. The scrollbar width leak check covers a related but distinct angle: scripts that send clicks and scrolls but fail to reproduce the varied timing and hesitation of real users.
Key Facts About BotRefund's Detection System
| Aspect | Detail |
|---|---|
| Number of independent checks | 106 independent checks used to build a picture of each visit |
| Reported accuracy | 99% accuracy, based on corroboration across browser, network, device, and behavior signals |
| How signals are combined | Each signal goes into a prediction AI that weighs the complete pattern rather than trusting a single rule |
| What a single signal means | One anomaly is evidence, not a verdict; it is cross-checked against other signals |
| Refund-ready report contents | Click IDs, campaign details, timestamps, session recordings, and signal-by-signal reasoning |
| Client refund success rate | 83% of clients recover funds from Google and Meta across 2,500+ audits |
| Signal categories | Browser, network, device, behavior, and attribution signals |
When This Advice Applies and When It Does Not
This implementation guidance applies if you are an advertiser or site owner using BotRefund to detect automated traffic and build evidence for ad-platform refund claims. It is most useful when you run paid campaigns on Google or Meta and need session-level proof that bots clicked your ads.
It does not apply if you are looking for a CDN, WAF, DDoS mitigation, or edge infrastructure replacement. BotRefund is a marketing-focused evidence layer, not an infrastructure product. If your requirement is edge protection, compare infrastructure providers separately. BotRefund can coexist with your existing edge layer; it does not require you to replace it.
It also does not apply if you need to detect bots solely from server-side log files. BotRefund's init-script check runs client-side, in the browser, because that is where automation tools leave their traces. Server-side logs catch basic scrapers but struggle with advanced botnets that use real browser engines.
Related Signals Worth Understanding
The Playwright Init Scripts check sits in the Evasion, Debugger, and Anti-Stealth Traps category. Other checks in this category look for different types of API patching and stealth behavior. The Clean Context Iframe check, for example, inspects the browser from within an iframe context to catch mismatches that might not show up in the main page context.
Biometric and behavioral checks cover a different angle. The scrollbar width leak check looks for scripts that send interactions without the natural variation in timing and movement that real people produce. Behavioral checks flag robotic linear mouse movements, absence of humanlike mouse tremor, superhuman input speeds under 1ms, grid-aligned movement patterns, and unnatural session durations.
Understanding these related signals helps you read BotRefund's session explanations. When a visit is flagged, the explanation will list which signals contributed and how they fit together. Knowing what each signal detects makes it easier to judge whether the flag is reliable.
Limitations of the Init Scripts Check
The init-scripts check cannot catch every type of bot. Sophisticated automation tools that use unmodified browser builds and avoid patching APIs may not trigger this specific signal. That is why BotRefund relies on 106 checks rather than one; a bot that evades the init-script check may still trip behavioral or network signals.
The check can also produce false positives for genuine visitors who use privacy extensions, script blockers, or unusual browser configurations. BotRefund handles this by treating the signal as evidence and cross-checking it, but you should be aware that browser-level checks are not perfectly clean signals on their own.
Finally, the check only works if the script loads and executes on the visitor's browser. If a bot blocks third-party scripts entirely, the init-script signal will not fire. In that case, BotRefund relies on other signals that do not require client-side execution.
Frequently Asked Questions
Why does BotRefund use 106 checks instead of one?
Because no single browser signal reliably separates bots from humans. Privacy tools, corporate networks, and unusual devices can all produce anomalies that look like automation. By cross-checking 106 independent signals, BotRefund builds a pattern that is far more reliable than any individual check. The prediction AI weighs the complete picture rather than trusting a raw rule.
How long does it take for the init-script signal to produce useful data?
The script starts collecting data immediately after installation, but you need enough traffic volume for the patterns to become meaningful. For most sites, 24 to 48 hours of normal traffic is enough to see whether the signal is firing and contributing to session records. For sites with lower traffic, it may take longer to build a useful pattern.
When should I act on a flagged visit?
Act only when the flag is supported by multiple signals, not when it rests on a single anomaly. BotRefund's session explanations show which signals contributed to each flag. If the init-script signal is the only evidence, investigate further before excluding the visit or filing a refund claim.
What does it cost to use BotRefund?
BotRefund offers a free bot audit, and you can install the detection script at no cost. For details on paid plans and enterprise features, check the pricing page. The free audit gives you a starting point to see what BotRefund finds in your traffic before you commit to a paid tier.
What should I compare BotRefund against?
Compare it against other bot-detection and ad-fraud-evidence tools on the basis of signal breadth, report format, and refund-claim support. Some tools focus on edge protection or server-side filtering. BotRefund focuses on client-side evidence collection and refund-ready reporting for Google and Meta advertisers. If you need infrastructure protection, you may use BotRefund alongside a CDN or WAF rather than instead of one.
Can I use the init-script check with my existing Cloudflare or WAF setup?
Yes. BotRefund is an evidence layer, not an infrastructure replacement. It coexists with your existing edge protection. Your CDN or WAF handles request-level filtering and delivery, while BotRefund collects browser-level evidence after the request reaches the page. Many advertisers use both.
What happens if a bot blocks the init script?
If a bot blocks third-party scripts, the init-script signal will not fire for that session. BotRefund still has other signals that do not depend on client-side execution, including network and attribution checks. A session with no init-script data is not automatically cleared; it is simply evaluated on the signals that are available.
Further reading and comparison sources
These external sources provide additional context for evaluating the topic. Their inclusion is not an endorsement.
How BotRefund can help
BotRefund gives you 106 independent browser, network, device, and behavioral checks that feed into a prediction AI, so the Playwright Init Scripts signal is never judged in isolation. Each flagged visit comes with a session-by-session explanation that lists which signals contributed and how they fit together.
If you run paid campaigns on Google or Meta, BotRefund turns each finding into a refund-ready report with click IDs, campaign details, timestamps, session recordings, and signal-by-signal reasoning. Across 2,500+ audits, 83% of clients have recovered funds from Google and Meta.
One limitation to keep in mind: BotRefund is an evidence layer for advertisers, not a CDN or WAF replacement. If you need edge protection or DDoS mitigation, use BotRefund alongside your existing infrastructure rather than instead of it.