HTML Nesting Validator

Open HTML Nesting Validator on Happytails.ai. This view has the same page content and links, with explicit tool capabilities. Read the processing notes before using a tool.

Tool capabilities

{
  "id": "html-nesting-validator",
  "category": "developer-tools",
  "built": true,
  "requirements": "Input is limited to 200000 characters. Results are computed locally and exported as JSON.",
  "implementation": {
    "fields": [],
    "inputMaxLength": 200000,
    "inputErrorCode": "STRUCTURED_TEXT_TOO_LONG",
    "registrationFamily": "html-nesting-validator",
    "note": "Check common HTML tag nesting errors locally.",
    "experience": {
      "automatic": false,
      "single": false,
      "inputMaxLength": 200000,
      "inputMode": "text",
      "label": "HTML source",
      "placeholder": "<p>Hello <strong>world</strong>.</p>",
      "help": "Paste HTML markup, not a website URL. Up to 200,000 characters. Review the settings before running.",
      "helpParts": [
        "Paste HTML markup, not a website URL.",
        "Up to 200,000 characters.",
        "Review the settings before running."
      ],
      "action": null
    },
    "mode": "explicit",
    "interactive": false
  },
  "execution": "Browser interface",
  "api": null,
  "browser_agent": {
    "supported": true,
    "name": "run_current_tool",
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}

Page guide