# Jeremylongshore Claude Code Plugins Plus Skills Cors Policy Validator > Overview - Skill: `tomevault-io/jeremylongshore-claude-code-plugins-plus-skills-cors-policy-` (Agent Skill, multi-file: 2 files) - Install (CLI): `npx skillmds@latest add tomevault-io/jeremylongshore-claude-code-plugins-plus-skills-cors-policy-` - Raw SKILL.md: https://api.skillmd.com/api/skills/tomevault-io/jeremylongshore-claude-code-plugins-plus-skills-cors-policy-/raw - Safety review: pending (external: skill-scanner PASS, skillspector PASS) - Works with: Claude Code, Claude.ai, OpenAI Codex - Category: Coding & Dev Tools - Author: tomevault-io (https://skillmd.com/u/tomevault-io) - Updated: 2026-09-17 - Page: https://skillmd.com/skills/tomevault-io/jeremylongshore-claude-code-plugins-plus-skills-cors-policy- --- ## Overview This skill empowers Claude to assess the security and correctness of CORS policies. By leveraging the cors-policy-validator plugin, it identifies misconfigurations and potential vulnerabilities in CORS settings, helping developers build more secure web applications. ## How It Works 1. **Analyze CORS Configuration**: The skill receives the CORS configuration details, such as headers or policy files. 2. **Validate Policy**: It utilizes the cors-policy-validator plugin to analyze the provided configuration against established security best practices. 3. **Report Findings**: The skill presents a detailed report outlining any identified vulnerabilities or misconfigurations in the CORS policy. ## When to Use This Skill This skill activates when you need to: - Validate a CORS policy for a web application. - Check the CORS configuration of an API endpoint. - Identify potential security vulnerabilities in existing CORS implementations. ## Examples ### Example 1: Validating a CORS Policy File User request: "Validate the CORS policy in `cors_policy.json`" The skill will: 1. Read the `cors_policy.json` file. 2. Use the cors-policy-validator plugin to analyze the CORS configuration. 3. Output a report detailing any identified vulnerabilities or misconfigurations. ### Example 2: Checking CORS Headers for an API Endpoint User request: "Check CORS headers for the API endpoint at `https://example.com/api`" The skill will: 1. Fetch the CORS headers from the specified API endpoint. 2. Use the cors-policy-validator plugin to analyze the headers. 3. Output a report summarizing the CORS configuration and any potential issues. ## Best Practices - **Configuration Source**: Always specify the source of the CORS configuration (e.g., file path, URL) for accurate validation. - **Regular Validation**: Regularly validate CORS policies, especially after making changes to the application or API. - **Heuristic Analysis**: Consider supplementing validation with manual review and heuristic analysis to catch subtle vulnerabilities. ## Integration This skill can be integrated with other security-related plugins to provide a more comprehensive security assessment. For example, it can be used in conjunction with vulnerability scanning tools to identify potential cross-site scripting (XSS) vulnerabilities related to CORS misconfigurations. --- > Converted and distributed by [TomeVault](https://tomevault.io/claim/jeremylongshore) — claim your Tome and manage your conversions.