Number Guard

When to use

If a number affects money, a decision, a comparison, a deadline, a measurement, or a published claim, calculate it with a tool before presenting it. Use this workflow for tax, budgets, rates, percentages, statistics, dates, token costs, unit conversions, and symbolic work. Trivial single-digit sums may be answered directly.

Steps

1. Extract the supplied inputs, units, formula, and assumptions. If a missing input changes the answer, ask for it or label a scenario explicitly. If an input varies over time, use a dated source available within the task's permissions.
2. Inspect the calculator or code execution tools available in this session. Choose the operation by the question below. Use the tool's actual schema; these are operation categories, not required API names. A calculator MCP, a spreadsheet calculation tool, or local code execution can serve the same purpose. codecalc is one optional code execution tool.
3. Run the calculation. Use decimal strings or exact fractions for decimal money and ratios. Specify rounding mode, decimal places, and the stage where rounding occurs. Use a calendar and time-zone library for dates; use a symbolic tool when an exact symbolic result is needed.
4. Read the tool's result and successful completion signal. Check units, denominator, sign, and order of operations against the question. If an error, missing runtime, or incomplete run prevents computation, report the limitation and the uncomputed formula.
5. Present the exact value and the rounded value with its framing. Keep an exact fraction when a decimal repeats; label any finite decimal approximation. If independent rounding creates a remainder in a split bill, show how the remainder is allocated and confirm the allocations total the rounded bill.

Question-to-tool map