sanitizing-user-inputs

Prevent XSS attacks by validating user input with strict typed schemas before processing, then sanitizing output for HTML context. Use an allowlist-based validation approach that rejects invalid data rather than trying to block known threats.

Define a Zod schema that enforces strict type and content rules for incoming data, validate the input against that schema before use, and throw errors on invalid entries. This validation-first approach returns fully typed results safe for downstream processing.

Sanitize user input by parsing it through a typed validation schema with allowlist rules that only accept expected formats and values. Combined with output encoding for the target context (HTML, URL, SQL), this stops injection attacks before they reach your application logic.

Yes. Zod is the primary tool for this Skill—define schemas that specify allowed types and formats, validate incoming data against those schemas, and receive typed results or errors. Zod integrates seamlessly into TypeScript applications for API and form processing.

Allowlists are more secure because they explicitly permit only known-safe formats and values, whereas blocklists try to exclude known threats and fail against new attack vectors. Allowlist validation catches unexpected input and prevents vulnerabilities by default.