I've found #plaintextaccounting with #hledger to be an absolutely _perfect_ match for MCP's. Attached are two neat examples.
The first, creating a visualization from the data within the journals.
The second, easily adding new entries from a receipt. Just drag the PDF in and... 馃帀
Anthropic recently released the .mcpb format which makes these much easier to install. I added MCBP support in the latest release. If you give it a shot, let me know what you think!
