101-tool math calculator via mcp-calculator — arithmetic, trig, stats, matrix, financial, geometry, numerical methods

mcp-calculator v1.0.2 — 101 mathematical tools across 10 categories

Install: npm install mcp-calculator Entry: build/index.js (stdio transport) 78 calls across 10 categories, 100% success, p50=0ms (pure computation), startup banner in Chinese

Tool Categories (101 tools total)

Key Observations

• All output is in Chinese (Mandarin) — startup: "已注册 101 个计算器工具", results: "加法运算结果" (addition result), "错误：除数不能为零！" (division by zero error)
• Sub-millisecond computation — pure math, no I/O; p50=0ms across 78 calls
• Triangle detection — automatically identifies right triangles ("直角三角形") and computes all angles
• Financial tools include investment advice — NPV returns "投资建议" (investment recommendation), IRR shows profitability indicator
• Cross-verified results — factorial(10)=3628800 ✓, C(10,3)=120 ✓, gcd(12,18,24)=6 ✓, 1mi=1.609km ✓, 100°C=212°F ✓, |3+4i|=5 ✓, det[[1,2],[3,4]]=-2 ✓, IRR=8.8963% ✓

Gotchas

• ⚠️ Polynomial coefficients are LOW-to-HIGH order — [a₀, a₁, a₂] means a₀ + a₁x + a₂x². So [0,0,1] = x², NOT [1,0,0]. Confirmed: ∫₀¹ x²dx with [0,0,1] returns 0.333 ✓
• ⚠️ Unit conversion uses SHORT ENUM values — km not kilometer, kmh not km/h, m2 not square_meter, lb not pound. Using full names returns MCP validation error with enum list
• ⚠️ Volume conversion has NO `gal`/`gallon` option — options: ml, l, m3, cm3, in3, ft3 (US gallon not supported)
• ⚠️ `isPrime` returns Chinese text — "97 是素数" (97 is prime) / "100 不是素数（偶数）" (100 is not prime, even) — not boolean true/false
• `sqrt(-1)` returns graceful error — "负数不能开平方根！" (negative numbers can't have square root)
• `divide(10,0)` returns graceful error — "除数不能为零！" (divisor cannot be zero)
• Matrix inverse uses fixed-point format — [-2.000000, 1.000000] not exact fractions
• `stdDev` has `sample` boolean param — false for population, true for sample standard deviation

Verified Trace (78 calls)

Arithmetic (7): add(17,25)=42, divide(10,3)=3.333, divide(10,0)=error, power(2,10)=1024, sqrt(144)=12, cbrt(27)=3, modulo(17,5)=2 — all ✅

Trig (4): sin(π/2)=1, cos(0)=1, degToRad(180)=π, atan2(1,1)=π/4 — all ✅

Log (3): ln(e)=1, log10(1000)=3, log(8,2)=3 — all ✅

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