why the polygon split into 2 parts?

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tippecanoe -o census_2018_us_block.mbtiles -zg --drop-densest-as-needed census_2018_us_block.geojson

I use above parameter,

at detailed zoom level, like 12, 13, one polygon split into 2 parts.
when I zoom out to 5, 6, the splitted polygon merge back to one polygon.

I understand is because at zoom 13, one tile is not big enough to capture all polygon.
In another word, 1 big polygon spread into 2 or more tiles.

What parameter should I use to avoid such problem?

Where is document teach me how to use each parameters?

Start by reproducing the behavior with the provided tippecanoe command and census_2018_us_block.geojson, comparing zoom levels 5–6 with 12–13. Check the available parameter documentation and determine whether a setting can prevent the polygon from appearing split across tiles; document the expected behavior and relevant option if one exists.

Written by the indexing model from the issue text.