Your AI Probably Can't Build a Pivot Table — Here's What Can

A real-world test found that a generic Python/openpyxl session failed to build a proper Excel pivot table, while an agent using Kookerella.FsOpenXmlDsl's MCP server succeeded, with results verified by unzipping the .xlsx files to inspect the XML parts. The test highlights the limitations of common AI coding approaches for complex Excel tasks.

AI agents get asked to build Excel reports constantly. When a Python-based agent gets that request, it almost always reaches for the same library: openpyxl https://openpyxl.readthedocs.io/ . So I ran a real test: give the same task to a a generic Python/openpyxl session and b an agent using Kookerella.FsOpenXmlDsl https://github.com/Kookerella-Ltd/Kookerella.FsOpenXmlDsl ’s MCP server, and look at what actually landed in the resulting file - not what either session claimed it did. Everything below is real: real code, run for real, with the resulting .xlsx files inspected by unzipping them an .xlsx is just a zip of XML parts to check what’s objectively inside, rather than trusting either tool’s own success message.