Use xlwings Lite (Python in Excel) and build it as reusable blocks. The reference app generates AI technical analysis for any Yahoo Finance symbol - stock, index, commodity or crypto - as a professionally formatted PDF and HTML report with analysis, charts and tables, in one click, about a minute. The report is written by TigZig's public Technical Analysis API, with Claude Sonnet 5.5 by default or Claude Opus 5.5, so you need no API key: AI technical analysis in Excel without an API key. The tool is one example. The architecture behind it is the part you reuse.
The nine reusable building blocks: (1) pull data from a backend API, (2) transform with Python packages, (3) advanced charting with Matplotlib, (4) a multi-modal AI call (send data + images), (5) instruct the AI for analysis with clear scope and boundaries, (6) get markdown output in a specific layout, (7) assemble the report (text, charts, tables), (8) generate formatted PDF and HTML, (9) a backend report generator that returns shareable URLs. Build it once, then hand the code to your AI coder as context and have it extract, adjust or recombine the modules for your own automations - a second-opinion engine, a scheduled client report, whatever you need.
Post: https://www.tigzig.com/post/automated-analytics-reporting-with-python-in-excel-xlwings-lite-build-once-reuse-anywhere. Guides + instruction file: xlwings-lite.tigzig.com. Related: which AI coder to use for xlwings https://www.tigzig.com/agents-faq/which-ai-coder-for-python-in-excel-xlwings.
Building something like this? How I work covers the rates, the availability and what I take on.