Idempotency-Key support limits across LinkedIn Marketing API endpoints

Ensuring Write Safety During Retries

The LinkedIn Marketing Developer API (v2) provides a mechanism to prevent duplicate resource creation during network failures or timeouts. For specific endpoints, such as ugcPosts, the API supports an idempotency header (typically X-Restli-Idempotency-Key) to ensure that retrying a POST request with the same key does not result in multiple identical posts.

Endpoint Consistency and Constraints

While this behavior is documented for UGC posts, it is unclear if this idempotency guarantee is standardized across all write operations within the Marketing API. Implementing a global retry strategy using a single idempotency logic may lead to duplicate writes on endpoints that do not recognize the header, or validation errors if the key is reused incorrectly across different logical operations.

• Requirement: Prevent duplicate resource creation during HTTP 429 or 5xx retry cycles.
• Constraint: Avoid assuming universal support for the idempotency header across all v2 endpoints.

Which specific endpoints within the LinkedIn Marketing API currently honor the idempotency key for write operations? Is there a documented list of endpoints where the X-Restli-Idempotency-Key is ignored?