Nansen Historical Who Bought Sold

Use this endpoint when you need historical (not current) buy/sell breakdowns per trader for a specific token, especially when temporal accuracy of labels matters — i.e., you want smart money classification as it existed at the end date, not today's labels. Prefer over /tgm/who-bought-sold when you need an explicit date range rather than a rolling window, or when gross volume metrics are needed alongside directional volumes.

• Missing required fields (chain, token_address, date_range) returns 422 validation error
• Unsupported chain value returns enum validation error
• Invalid token address format returns error
• Date range with date_from after date_to returns error
• Token with no trading activity in the date range returns empty data array
• Rate limiting or authentication failure returns 401/429
• Pagination cursor out of bounds returns empty results