check_performance_budget

Evaluate website performance against predefined budgets for metrics like FCP, LCP, TBT, CLS, and Speed Index. Use to ensure compliance with performance thresholds for optimal user experience.

Instructions

Check if website performance meets specified budget thresholds

Input Schema

Name	Required	Description	Default
`budget`	Yes
`device`	No	Device to emulate (default: desktop)	desktop
`url`	Yes	URL to audit

Input Schema (JSON Schema)

{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "additionalProperties": false,
  "properties": {
    "budget": {
      "additionalProperties": false,
      "properties": {
        "cumulativeLayoutShift": {
          "description": "CLS budget",
          "minimum": 0,
          "type": "number"
        },
        "firstContentfulPaint": {
          "description": "FCP budget in milliseconds",
          "minimum": 0,
          "type": "number"
        },
        "largestContentfulPaint": {
          "description": "LCP budget in milliseconds",
          "minimum": 0,
          "type": "number"
        },
        "performanceScore": {
          "description": "Score threshold (0-100)",
          "maximum": 100,
          "minimum": 0,
          "type": "number"
        },
        "speedIndex": {
          "description": "Speed Index budget in milliseconds",
          "minimum": 0,
          "type": "number"
        },
        "totalBlockingTime": {
          "description": "TBT budget in milliseconds",
          "minimum": 0,
          "type": "number"
        }
      },
      "type": "object"
    },
    "device": {
      "default": "desktop",
      "description": "Device to emulate (default: desktop)",
      "enum": [
        "desktop",
        "mobile"
      ],
      "type": "string"
    },
    "url": {
      "description": "URL to audit",
      "type": "string"
    }
  },
  "required": [
    "url",
    "budget"
  ],
  "type": "object"
}

Lighthouse MCP

check_performance_budget

Instructions

Input Schema

Input Schema (JSON Schema)

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