---
name: calculator
description: "Perform basic arithmetic operations: addition, subtraction, multiplication, and division"
---

# calculator

Perform basic arithmetic operations: addition, subtraction, multiplication, and division.

## Input

The input is a JSON object provided via standard input:

```json
{
  "a": 10,
  "op": "+",
  "b": 5
}
```

### Parameters

- `a` (number, required): First operand
- `op` (string, required): Operator, one of `+`, `-`, `*`, `/`
- `b` (number, required): Second operand

## Output

Returns a JSON object to standard output:

```json
{
  "result": 15
}
```

## Errors

On failure, returns a JSON object:

```json
{
  "error": "division by zero"
}
```

## Notes

- This skill is non-interactive.
- Output is always valid JSON.
- No output is written to stderr.