Validating Inputs

Validate external data with type, range, and format checks.

41|27|Updated Oct 6, 2025

Search Tags:#security #validation #error-handling #quality-assurance #input-processing #defensive-programming

Ready to run

npx skills add https://github.com/obra/clank --skill validating-inputs-obra

💬 Prompt for ChatGPT / Claude Chat▼

Please help me install this Agent Skill.
Skill: Validating Inputs
Source: https://github.com/obra/clank/tree/main/skills/coding/validating-inputs
Command: npx skills add https://github.com/obra/clank --skill validating-inputs-obra

SYSTEM DOCUMENTATION & REQUIREMENTS

What problem does it solve?

This Skill prevents software failures, security vulnerabilities, and data corruption by ensuring all external inputs are thoroughly validated before processing.

Core Features & Use Cases

Two-Level Defense: Combines assertions for internal invariants with error handling for external data.
Comprehensive Validation: Covers types, ranges, formats, lengths, and security constraints.
Use Case: When writing a function that calculates student grades, use this Skill to validate that all scores are numbers between 0-100 before performing calculations.

Quick Start

Use the Validating Inputs skill to check if this function properly validates all external parameters and handles edge cases.

Frequently Asked Questions about Validating Inputs

High-intent search queries and answers about installing and using this skill.

FAQPage Schema

How do I validate user input to prevent security vulnerabilities and data corruption?▼

Validate all external inputs—user data, API responses, database results, and file contents—by checking format, type, range, and length before processing. Apply explicit error handling and safe defaults across your codebase to block invalid data from corrupting downstream logic.

What's the best way to handle malformed data in production systems?▼

Use two-level defense: assertions for internal invariants to catch logic errors, and structured error handling for external data to ensure deterministic behavior. This approach prevents failures while maintaining data integrity under edge cases.

How do I check if a function properly validates all parameters before processing?▼

Review whether the function validates every external parameter for type, range, format, and security constraints, handles edge cases explicitly, and returns safe defaults or clear errors when validation fails.

When should I validate input versus trusting internal function calls?▼

Validate all data crossing system boundaries—user input, network payloads, database results, and file contents. Use assertions for values generated internally by your own code, which you control directly.

What defensive programming patterns prevent invalid inputs from reaching business logic?▼

Combine validation rules at entry points with structured exception paths that reject malformed data early. Assert preconditions on internal function inputs and implement format and range checks before any downstream processing occurs.