Fixed width file parser

Open Fixed width file parser 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": "fixed-width-file-parser",
  "category": "data-tools",
  "built": true,
  "requirements": "Widths count Unicode code points rather than bytes, grapheme clusters or visual columns. Every record must have exactly the total width. Tabs count as one character. The final newline terminates the preceding record. Up to 1,000,000 characters, 10,000 data records, 100 columns and 100,000 cells across the sources. Files for multi-source tools are limited to 4,000,000 bytes total. Reports retain at most 500 diagnostic findings and state any omitted count. CSV and JSON outputs are limited to 4,000,000 characters.",
  "implementation": {
    "fields": [
      {
        "key": "widths",
        "label": "Field widths (JSON)",
        "value": "[4, 8, 5]",
        "type": "textarea",
        "help": "Positive whole-number widths measured in Unicode code points."
      },
      {
        "key": "headers",
        "label": "Output column names (JSON)",
        "value": "[\"id\", \"name\", \"score\"]",
        "type": "textarea",
        "help": "One unique nonempty column name for every field width."
      },
      {
        "key": "trim",
        "label": "Field padding",
        "value": "Trim spaces",
        "type": "select",
        "values": [
          "Trim spaces",
          "Preserve"
        ]
      },
      {
        "key": "outputSafety",
        "label": "CSV output cells",
        "value": "Protect spreadsheet cells",
        "type": "select",
        "values": [
          "Protect spreadsheet cells",
          "Preserve original cells"
        ]
      }
    ],
    "live": true,
    "presentation": "metrics",
    "note": "Runs locally on your device. CSV requires unique nonempty headers. Up to 1,000,000 characters, 10,000 data records and 100,000 cells across inputs, with 100 columns. Quoted multiline cells are supported. Each JSON settings field is limited to 100,000 characters. Output files are bounded to 4,000,000 characters. Diagnostic reports contain at most 500 findings and disclose the omitted count. Every line must have exactly the total width. Trim spaces removes only ASCII spaces at each field edge; Preserve retains all padding. Widths are code points, not UTF-8 bytes, visual columns or grapheme clusters. A final newline terminates the previous record. Protect spreadsheet cells prefixes formula-like values, including negative numbers, with an apostrophe. Choose Preserve original cells only for a trusted import workflow.",
    "experience": {
      "automatic": true,
      "single": false,
      "inputMaxLength": 1000000,
      "inputMode": "text",
      "label": "Fixed-width records",
      "placeholder": "0001Alice   00012\n0002Bob     00009",
      "help": "Paste fixed-width records, one per line. Widths count Unicode code points. Results update as you type. Up to 1,000,000 characters.",
      "helpParts": [
        "Paste fixed-width records, one per line. Widths count Unicode code points.",
        "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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