Does the platform detect Paid partnerships via API when there is no hashtag or description disclosure?
How Winnin detects sponsored content using textual signals.

Primarily, detection is based on textual signals — titles and tags.
There may be additional API-based signals in certain cases (the system has evolved significantly over time), but the core methodology relies on the presence of identifiable disclosure terms.
If there is no textual indicator, detection becomes significantly more limited.