percentage
Calculate percentages: find percentages of values, increase or decrease amounts by percentages, and determine percentage changes between values.
Instructions
Perform percentage calculations: of, increase, decrease, or change.
Examples:
PERCENTAGE OF: 15% of 200 operation="of", value=200, percentage=15 Result: 30
INCREASE: 100 increased by 20% operation="increase", value=100, percentage=20 Result: 120
DECREASE: 100 decreased by 20% operation="decrease", value=100, percentage=20 Result: 80
PERCENTAGE CHANGE: from 80 to 100 operation="change", value=80, percentage=100 Result: 25 (25% increase)
Input Schema
| Name | Required | Description | Default |
|---|---|---|---|
| context | No | Optional annotation to label this calculation (e.g., 'Bond A PV', 'Q2 revenue'). Appears in results for easy identification. | |
| output_mode | No | Output format: full (default), compact, minimal, value, or final. See batch_execute tool for details. | full |
| operation | Yes | Type of calculation | |
| value | Yes | Base value | |
| percentage | Yes | Percentage amount (or new value for 'change') |
Input Schema (JSON Schema)
{
"properties": {
"context": {
"anyOf": [
{
"type": "string"
},
{
"type": "null"
}
],
"default": null,
"description": "Optional annotation to label this calculation (e.g., 'Bond A PV', 'Q2 revenue'). Appears in results for easy identification."
},
"operation": {
"description": "Type of calculation",
"enum": [
"of",
"increase",
"decrease",
"change"
],
"type": "string"
},
"output_mode": {
"default": "full",
"description": "Output format: full (default), compact, minimal, value, or final. See batch_execute tool for details.",
"enum": [
"full",
"compact",
"minimal",
"value",
"final"
],
"type": "string"
},
"percentage": {
"description": "Percentage amount (or new value for 'change')",
"type": "number"
},
"value": {
"description": "Base value",
"type": "number"
}
},
"required": [
"value",
"percentage",
"operation"
],
"type": "object"
}
Implementation Reference
- src/vibe_math_mcp/tools/basic.py:105-145 (handler)The handler function implementing percentage calculations for operations: 'of', 'increase', 'decrease', 'change'.async def percentage( operation: Annotated[ Literal["of", "increase", "decrease", "change"], Field(description="Type of calculation") ], value: Annotated[float, Field(description="Base value")], percentage: Annotated[ float, Field(description="Percentage amount (or new value for 'change')") ], ) -> str: """Perform percentage calculations.""" try: if operation == "of": result = (percentage / 100) * value explanation = f"{percentage}% of {value}" elif operation == "increase": result = value * (1 + percentage / 100) explanation = f"{value} increased by {percentage}%" elif operation == "decrease": result = value * (1 - percentage / 100) explanation = f"{value} decreased by {percentage}%" elif operation == "change": # percentage is actually the new value in this case if value == 0: raise ValueError("Cannot calculate percentage change from zero") result = ((percentage - value) / value) * 100 explanation = f"Percentage change from {value} to {percentage}" else: raise ValueError(f"Unknown operation: {operation}") return format_result( result, { "operation": operation, "value": value, "percentage": percentage, "explanation": explanation, }, ) except Exception as e: raise ValueError(f"Percentage calculation failed: {str(e)}")
- src/vibe_math_mcp/tools/basic.py:78-104 (registration)Registers the 'percentage' MCP tool with name, description, and annotations.@mcp.tool( name="percentage", description="""Perform percentage calculations: of, increase, decrease, or change. Examples: PERCENTAGE OF: 15% of 200 operation="of", value=200, percentage=15 Result: 30 INCREASE: 100 increased by 20% operation="increase", value=100, percentage=20 Result: 120 DECREASE: 100 decreased by 20% operation="decrease", value=100, percentage=20 Result: 80 PERCENTAGE CHANGE: from 80 to 100 operation="change", value=80, percentage=100 Result: 25 (25% increase)""", annotations=ToolAnnotations( title="Percentage Calculator", readOnlyHint=True, idempotentHint=True, ), )
- Pydantic schema definitions for the tool's input parameters: operation, value, percentage.operation: Annotated[ Literal["of", "increase", "decrease", "change"], Field(description="Type of calculation") ], value: Annotated[float, Field(description="Base value")], percentage: Annotated[ float, Field(description="Percentage amount (or new value for 'change')") ], ) -> str: