The Agent Skills Directory

[SAFE]: The skill is a technical guide for implementing idempotency in backend systems. It provides valid architectural patterns and code templates for Express.js, FastAPI, and Spring Boot.
[SAFE]: No obfuscation, data exfiltration, or malicious persistence mechanisms were found. All referenced code and libraries are industry-standard tools (e.g., Redis, PostgreSQL, DynamoDB).
[INDIRECT_PROMPT_INJECTION]: The skill documents the storage and retrieval of client-provided headers and request bodies, which constitutes a potential data ingestion surface for indirect prompt injection if that data is later processed by an agent without sanitization.
Ingestion points: Idempotency-Key request header and req.body payload (SKILL.md, references/idempotency-middleware.md).
Boundary markers: Not applicable for this architectural pattern.
Capability inventory: Code templates include database writes (PostgreSQL, DynamoDB) and cache operations (Redis).
Sanitization: The skill provides logic for strict UUID validation for the header key, reducing the surface for malformed inputs.

backend-idempotency