JSON Merge Patch tester

Open JSON Merge Patch tester 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": "json-merge-patch-tester",
  "category": "developer-tools",
  "built": true,
  "requirements": "Up to 1,000,000 characters, 50,000 values and 64 nesting levels per document. UTF-8 file imports are limited to 1 MB. Processing runs in a local worker with a 10-second timeout and a bounded work budget. Duplicate keys and numbers that cannot be preserved safely are rejected.",
  "implementation": {
    "fields": [
      {
        "key": "change",
        "label": "Merge patch",
        "value": "{\n  \"profile\": {\"city\": null},\n  \"tags\": [\"new\"],\n  \"score\": 8\n}",
        "type": "text"
      }
    ],
    "inputMaxLength": 1000000,
    "inputErrorCode": "PATCH_INPUT",
    "note": "Apply RFC 7396 JSON Merge Patch locally. A null object member removes that member. Arrays and non-object patches replace the target value in full. Formatting and key order may change. This tool does not send an API request.",
    "experience": {
      "automatic": false,
      "single": false,
      "inputMaxLength": 1000000,
      "inputMode": "text",
      "label": "Original JSON document",
      "placeholder": "{\n  \"profile\": {\"name\": \"Alex\", \"city\": \"Lisbon\"},\n  \"tags\": [\"old\"],\n  \"active\": true\n}",
      "help": "Paste the original JSON document. Use the second editor for the merge patch or target document. Up to 1,000,000 characters. Review the settings before running.",
      "helpParts": [
        "Paste the original JSON document. Use the second editor for the merge patch or target document.",
        "Up to 1,000,000 characters.",
        "Review the settings before running."
      ],
      "action": null
    },
    "mode": "explicit",
    "interactive": true
  },
  "execution": "Browser interface",
  "api": null,
  "browser_agent": {
    "supported": false,
    "name": null,
    "discovery": "WebMCP on the human page in a supporting browser",
    "verification": "See audit/API-AUDIT.md; availability is not verification"
  }
}

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