# Calculator Skill

> Mathematical calculation skill for computing arithmetic expressions, trigonometry, logarithms, and complex math. Use EXCLUSIVELY for math calculations: sin, cos, tan, sqrt, log, exponents, etc.

- Skill: `smallnest/calculator-skill` (Agent Skill, multi-file: 3 files)
- Install (CLI): `npx skillmds@latest add smallnest/calculator-skill`
- Raw SKILL.md: https://api.skillmd.com/api/skills/smallnest/calculator-skill/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Coding & Dev Tools
- License: MIT
- Author: smallnest (https://skillmd.com/u/smallnest)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/smallnest/calculator-skill

---


# Calculator Skill

A specialized mathematical calculator skill for computing arithmetic expressions, trigonometric functions, logarithms, and advanced math operations.

## ⚠️ IMPORTANT: Use This Skill For Math Calculations ONLY

This skill is designed **EXCLUSIVELY** for mathematical calculations. Use it when:
- The user asks to calculate or compute mathematical expressions
- Trigonometric operations are needed (sin, cos, tan, radians, degrees)
- Basic arithmetic is required (addition, subtraction, multiplication, division)
- Advanced operations are needed (exponents, square roots, logarithms)
- Complex expressions need to be evaluated
- Keywords: calculate, compute, math, trigonometry, sin, cos, tan, sqrt, log, radians

## Supported Operations

### Basic Arithmetic
- Addition: `5 + 3`
- Subtraction: `10 - 4`
- Multiplication: `6 * 7`
- Division: `20 / 4`

### Trigonometric Functions ⭐
- `sin(x)` - Sine of x (x in radians)
- `cos(x)` - Cosine of x (x in radians)
- `tan(x)` - Tangent of x (x in radians)
- `radians(x)` - Convert degrees to radians
- `degrees(x)` - Convert radians to degrees

### Advanced Operations
- Exponentiation: `2 ** 8` (2 to the power of 8)
- Square root: `sqrt(16)`
- Logarithms: `log(100)`, `log10(100)`
- Absolute value: `abs(-5)`

### Constants
- Pi: `pi` (3.14159...)
- Euler's number: `e` (2.71828...)

For a complete list of all available functions, see [references/functions.md](references/functions.md).

## How to Use

1. Identify the mathematical operation the user wants to perform
2. Format the expression as a valid mathematical expression
3. Run the calculation script with the expression as an argument
4. Return the result to the user

### Running the Script
```bash
python scripts/calculate.py "expression"
```

## Quick Examples

### Trigonometry (This Skill's Specialty!) ⭐
```bash
python scripts/calculate.py "sin(radians(30))"
# Result: 0.5

python scripts/calculate.py "cos(0)"
# Result: 1.0

python scripts/calculate.py "tan(radians(45))"
# Result: 1.0
```

### Basic Calculation
```bash
python scripts/calculate.py "125 + 237"
# Result: 362
```

### Complex Expression
```bash
python scripts/calculate.py "2**10 / 4"
# Result: 256.0
```

For more detailed examples across different domains, see [references/examples.md](references/examples.md).

## Additional Resources

- **[references/REFERENCE.md](references/REFERENCE.md)** - Complete technical reference and implementation details
- **[references/functions.md](references/functions.md)** - Full list of supported mathematical functions
- **[references/examples.md](references/examples.md)** - Domain-specific calculation examples

## Edge Cases and Error Handling

The script handles common mathematical errors:
- **Division by zero:** Returns an error message
- **Invalid expressions:** Reports syntax errors clearly
- **Undefined operations:** Catches mathematical domain errors
- **Invalid input:** Validates the expression before evaluation

## Safety

The script uses Python's restricted `eval()` to safely evaluate mathematical expressions without executing arbitrary code. Only mathematical operations are allowed.