AG Charts provides a zoom event - https://ag-grid.com/charts/r/events/#zoom - which is fired whenever the zoom level or position changes. This event gives you the range and ratio of the axes currently within the viewport.

This event is also fired when the zoom is reset - either by clicking the 'reset' button or by double-clicking an empty area on the canvas.

There is currently no way to distinguish how the zoom was triggered. However, you can often infer it by looking at the range and ratio values provided. For example a ratio of [0,1] indicates no zoom is applied and suggests a reset.

Could you share more about why it matters for your use case to know the exact interaction? That might help in suggesting a workaround.