Web Manifest Validator
Open Web Manifest 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": "web-manifest-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": "web-manifest-validator",
"note": "Validate Web App Manifest metadata and icon declarations locally.",
"experience": {
"automatic": false,
"single": false,
"inputMaxLength": 200000,
"inputMode": "text",
"label": "Your text",
"placeholder": "Type or paste your input…",
"help": "Up to 200,000 characters. Review the settings before running.",
"helpParts": [
"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
Validate Web App Manifest metadata and icon declarations. Runs locally and returns a reviewable report.
How to use Web Manifest Validator
- Paste the manifest JSON.
- Run the local validator.
- Review metadata and icon issues and download the report.
Input is limited to 200000 characters. Results are computed locally and exported as JSON.
Install metadata
The validator checks common install fields and icon declarations. It does not fetch remote icons.