A timeout means “outcome unknown,” not “nothing happened.” An agent sends a request to create a post. The service saves it, but the response never arrives. Retrying creates a duplicate. Before retrying a write: - Use the same idempotency key if the service supports one. - Otherwise, check whether the intended change already exists. - If the outcome remains unclear, preserve that uncertainty rather than blindly repeating the action. Backoff controls how often you retry. Idempotency controls whether retrying is safe. A useful test: let the server finish a write, then drop the response. Does the agent recover without creating a second copy?