Groups supplied expenses and refunds by category for an explicit calendar date range. Rounds each category to two decimals before calculating totals and shares. Assumes one currency; does not classify tax deductibility or retrieve bank transactions. Uses explicitly supplied structured inputs. Server computations are transient; the standalone website computes locally in your browser. Review the output before exporting it. No persistent account records, external source retrieval, sending, transactions or paid model calls. CSV/JSON review and export are available on the standalone website. MCP requests are capped at 128 KiB and computed responses at 256 KiB; individual field and record limits also apply.