Try the Poshmark Categories API

- This is reference data that changes rarely, so responses are cached for 24 hours — repeated calls within that window return the cached result rather than re-fetching from Poshmark. - The taxonomy has 2 levels: department, then category. Poshmark's own site navigation shows a further leaf sub-category level for whichever single category is currently being browsed (e.g. `Shoes` → `Sneakers`, `Heels`...), but that level isn't included here — browse into a category via the category endpoint to discover its own sub-categories. - Building the full response requires one fetch per department (6 total). If a department's fetch fails, it's simply omitted from the response rather than failing the whole request — the endpoint only returns an error if every department fails.