Idempotent Write Strategy: Unique Client ID vs. Server-Side State Check

Stack Overflow Post Creation Retries

The goal is to ensure a single post is created despite network retries on the Stack Exchange API's POST /posts endpoint.

Constraint Uncertainty

The API lacks documented idempotency, meaning standard client retries risk duplicate content.

• Should the client enforce idempotency using a unique request identifier header?
• Or should the client rely on a server-side check against content uniqueness prior to final write?