What are the four layers of validation used in this skill?

The four layers are Entry Point (rejecting invalid input at API boundaries), Business Logic (ensuring data makes sense for specific operations), Environment Guards (preventing dangerous actions in specific contexts like testing), and Debug Instrumentation (capturing context for forensics).

What is the primary goal of the Defense-in-Depth skill?

The primary goal is to make bugs structurally impossible by ensuring data is validated at every single layer it passes through, rather than relying on a single point of failure.

How does this differ from standard input validation?

Standard validation usually happens once at the entry point. Defense-in-depth assumes that single checks can be bypassed by refactoring, mocks, or different code paths, and adds redundant checks throughout the execution flow.

When should I use the Environment Guards layer?

Environment guards are best used to prevent dangerous operations, such as executing 'git init' or database wipes, in contexts like automated testing or specific deployment environments where those actions should be restricted.

Defense-in-Depth Validation

Name: Defense-in-Depth Validation
Author: carlopezzuto

bycarlopezzuto

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セキュリティとテスト

Hardens software reliability by implementing multi-layered data validation across system boundaries to eliminate structural bugs.

This skill provides a systematic framework for hardening software by implementing defense-in-depth validation across four critical layers: entry points, business logic, environment guards, and debug instrumentation. By verifying data at every stage of its lifecycle, it ensures that edge cases, refactoring errors, or mocked tests cannot bypass safety checks, making specific classes of bugs structurally impossible to reproduce. This approach is particularly effective for preventing deep execution failures caused by invalid data propagating through complex workflows.

主な機能

01Automated data flow tracing and checkpoint mapping

02Four-layer validation architecture (Entry, Business, Environment, Debug)

03Context-aware environment guards to prevent dangerous operations

04Structural bug prevention strategies and implementation patterns

05Debug instrumentation for enhanced forensic logging and error recovery

060 GitHub stars

ユースケース

01Preventing accidental file system operations or destructive commands during testing

02Hardening API boundaries and business logic against malformed or malicious inputs

03Securing complex data pipelines where failures occur deep within the execution stack

What are Skills?·How to Install

Install with 🐟 Skill.Fish

npx skillfish add carlopezzuto/agents defense-in-depth

For use in Claude.ai and ChatGPT

Download Skill