About Script Sentinel
Script Sentinel is an automated Content Security Policy (CSP) Generator and website security scanner built for developers, security engineers, and organizations that need accurate, production-ready CSP headers.
Our mission is to make web security accessible, automated, and transparent. Far too many security tools output generic or incomplete CSPs that break functionality or miss critical vulnerabilities. Script Sentinel bridges that gap by providing a dynamic auditing engine paired with a developer-friendly interface that highlights unsafe directives, identifies mixed-content issues, scores your security posture, and updates in real time as you fine-tune your policy. With clear explanations, live previews, and automated hashing of inline scripts and styles, Script Sentinel empowers you to generate a Content Security Policy that is not only secure but production ready.
Why We Built Script Sentinel
Most developers know CSPs are important, but creating them manually is tedious, error-prone, and time-consuming. Traditional scanners fail to account for dynamic JS, third-party CDNs, hidden requests, or evolving site behavior. We built Script Sentinel to remove the guesswork and give developers a clear, accurate picture of what their websites load behind the scenes.
Content Security Policy Headers Explained
A Content Security Policy header is an HTTP response header that instructs the browser which sources are allowed to load and execute content on a web page. By explicitly defining trusted origins for scripts, styles, images, fonts, frames, and network connections, CSP headers help prevent cross-site scripting (XSS), data injection attacks, and unauthorized third-party code execution.
When properly configured, a CSP header acts as a powerful client-side enforcement layer. Even if an attacker discovers a vulnerability in your application, the browser will block malicious scripts that are not explicitly permitted by the policy. Script Sentinel automatically analyzes real website behavior and generates production-ready CSP headers that reflect how your site actually operates reducing breakage while maximizing security.
Our Vision
We believe CSP adoption should be simple, powerful, and error-free. Script Sentinel aims to become the definitive tool for CSP development by combining automation, intelligence, and usability.
What Makes Script Sentinel a Best-in-Class CSP Generator?
Script Sentinel also functions as a CSP validator, helping teams identify insecure directives before deployment.
- Automated discovery of scripts, styles, images, fonts, and connections
- Inline script and style hashing (SHA-256 / SHA-384 / SHA-512)
- Detection of unsafe CSP directives
- Mixed-content and insecure request detection
- Production-ready Content Security Policy headers
- CSP validation and analysis to identify unsafe or overly permissive directives
Frequently Asked Questions (FAQ)
Script Sentinel is an automated Content Security Policy (CSP) generator and website security scanner. It analyzes how your website behaves, what it loads, what network connections it makes, and what inline scripts or styles it runs and then produces a hardened CSP tailored to your exact site structure. It also highlights risky directives, detects mixed-content issues, and provides a real-time security score.
Script Sentinel uses a headless Chrome instance to load your website the same way a real user would. As it crawls the page, it captures:
- All external scripts, styles, images, fonts, and media
- Inline scripts and inline styles
- Frames, iframes, and embeds
- XHR, WebSocket, and fetch calls
- Redirects and cross-origin requests
- Server-provided CSP headers
- Mixed-content issues (HTTP content loaded on HTTPS pages)
This raw data is processed into a structured resource map, transformed into CSP directives, optimized, and scored. The scanner never stores your website data permanently—everything is processed in memory and remains private to your session.
A Content Security Policy is a powerful browser security feature that helps protect your site from:
- Cross-site scripting (XSS)
- Data injection attacks
- Malicious third-party scripts
- Insecure content loading
A CSP tells the browser exactly which domains are allowed to load scripts, images, fonts, frames, styles, and network connections. Anything not explicitly allowed is blocked.
CSPs dramatically reduce attack surfaces by enforcing strict rules on what can execute on your site. With a strong CSP in place, even if an attacker finds a vulnerability, the browser will reject unauthorized scripts or injection attempts.
Effective CSPs improve:
- Cross-site scripting defense
- Content integrity
- Third-party script safety
- Mixed-content protection
- Overall site trustworthiness
For best practices and standards view the OWASP Security Cheat Sheets and Content Security Policy documentation (MDN)
A secure CSP typically includes the following:
- ✔ A strict
default-src— usually'none'or'self'. - ✔ A tightly defined
script-src— ideally with nonces or SHA hashes. - ✔ No wildcards (
*) except where absolutely necessary. - ✔ Explicit
image-src,style-src,font-src,frame-src, andconnect-srcdirectives. - ✔
upgrade-insecure-requestsfor mixed-content security. - ✔ Inline script/style hashing (SHA-256/384/512).
These ensure that your policy remains predictable, safe, and explicit.
Avoid these whenever possible:
- ✘
'unsafe-inline'— allows inline JS; breaks XSS protection. - ✘
'unsafe-eval'— allows dynamic code execution. - ✘
data:inscript-srcorobject-src— can be exploited for injection attacks. - ✘
blob:inscript-src— can weaken script integrity enforcement. - ✘ Domain wildcards (
*.example.comor*) — overly broad and easy to abuse. - ✘ Allowing third-party scripts without understanding their behavior.
Script Sentinel highlights these automatically in the live preview so you can identify and remove unsafe tokens.
By default, the scanner analyzes the page you provide and follows internal links up to a configurable depth (1–5 pages). This allows you to generate CSPs for single pages or multi-page site structures.
No. Script Sentinel only loads your page in a headless browser. It does not perform destructive actions, send form data, or change any information. It is a passive scanner.
Yes — Script Sentinel is designed specifically to generate production-ready CSP headers.
However, every site is unique, and you should:
- Review the allowed domains
- Remove unnecessary third-party sources
- Test the policy in
Report-Onlymode before enforcing it
The tool provides a strong, optimized baseline, but your security team should validate policies before deployment.
CSP is supported by all major browsers, including:
- Chrome
- Firefox
- Safari
- Edge
- Brave
Even older browsers support many of the essential directives.