JSONL validator

Open JSONL 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": "jsonl-validator",
  "category": "data-tools",
  "built": true,
  "requirements": "At most 10,000 physical lines and 100,000 characters per line. Up to 1,000,000 input characters, 50,000 values per JSON document and 64 nesting levels. Duplicate keys, negative zero and numbers that cannot safely retain their decimal value are rejected. Quote precision-sensitive numbers as strings. Formatting and object member order may change. Processing stays on your device. Each JSON Pointer is limited to 20,000 characters.",
  "implementation": {
    "fields": [],
    "live": true,
    "presentation": "metrics",
    "note": "Validate one JSON value per physical line and locate invalid records. Blank lines are invalid; a final newline is allowed. Duplicate keys and unsupported numbers are reported on their exact lines. At most 10,000 lines and 100,000 characters per line. The report lists up to 500 issues and counts any omitted issues. No normalized output is offered while invalid lines remain. Runs on your device. Up to 1,000,000 input characters, 50,000 values per JSON document and 64 nesting levels. Duplicate JSON keys, unsafe integers, negative zero and decimals that would change on JSON serialization are rejected rather than rounded. Quote precision-sensitive numbers as strings. Output whitespace and object-member order may change. Each JSON Pointer is limited to 20,000 characters.",
    "experience": {
      "automatic": true,
      "single": false,
      "inputMaxLength": 1000000,
      "inputMode": "text",
      "label": "JSONL records",
      "placeholder": "{\"name\":\"Ana\",\"score\":90}\n{\"name\":\"Bea\",\"score\":70}\n",
      "help": "Paste text to process locally. Review the result before downloading. Results update as you type. Up to 1,000,000 characters.",
      "helpParts": [
        "Paste text to process locally. Review the result before downloading.",
        "Results update as you type.",
        "Up to 1,000,000 characters."
      ],
      "action": null
    },
    "mode": "automatic",
    "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"
  }
}

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