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Merge CSV | agent view

The same page content and links, with explicit tool capabilities. Tools marked with an API can run directly through HTTP. Other tools require the browser interface or are not connected yet.

Tool capabilities

{
  "id": "merge-csv",
  "category": "spreadsheet-tools",
  "built": true,
  "requirements": "Append with header alignment; preserve types; source-file column option.",
  "implementation": {
    "fields": [
      {
        "key": "delimiter",
        "label": "CSV separator",
        "value": ",",
        "type": "select",
        "values": [
          ",",
          ";",
          "\t"
        ]
      }
    ],
    "files": true,
    "multiple": true,
    "input": false,
    "experience": {
      "automatic": false,
      "single": false,
      "label": "Your text",
      "placeholder": "Type or paste your input…",
      "help": "Up to 1,000,000 characters. Review the settings before running.",
      "action": null
    },
    "mode": "explicit",
    "interactive": false
  },
  "execution": "POST /api/v1/tools/merge-csv/run",
  "api": {
    "id": "merge-csv",
    "name": "Merge CSV",
    "category": "spreadsheet-tools",
    "description": "Append with header alignment.",
    "notes": "",
    "human_path": "/en/spreadsheet-tools/merge-csv/",
    "method": "POST",
    "endpoint": "/api/v1/tools/merge-csv/run",
    "schema_url": "/api/v1/tools/merge-csv",
    "input_schema": {
      "type": "object",
      "additionalProperties": false,
      "properties": {
        "input": {
          "type": "string",
          "maxLength": 1000000,
          "default": "",
          "description": "Plain text input. File tools use files instead unless otherwise documented."
        },
        "options": {
          "type": "object",
          "additionalProperties": false,
          "properties": {
            "delimiter": {
              "type": "string",
              "description": "CSV separator",
              "default": ",",
              "enum": [
                ",",
                ";",
                "\t"
              ]
            }
          }
        },
        "files": {
          "type": "array",
          "maxItems": 20,
          "items": {
            "type": "object",
            "required": [
              "name",
              "base64"
            ],
            "additionalProperties": false,
            "properties": {
              "name": {
                "type": "string",
                "maxLength": 200,
                "description": "Filename only, no path."
              },
              "mime": {
                "type": "string",
                "maxLength": 150
              },
              "bytes": {
                "type": "integer",
                "minimum": 0,
                "description": "Optional decoded byte count; must match content if supplied."
              },
              "base64": {
                "type": "string",
                "contentEncoding": "base64",
                "description": "File bytes as padded base64. Use the tool-specific limits.files_bytes value for the total decoded input size."
              }
            }
          }
        }
      }
    },
    "output_schema": {
      "type": "object",
      "required": [
        "tool",
        "result"
      ],
      "properties": {
        "tool": {
          "type": "string"
        },
        "result": {
          "type": "object",
          "required": [
            "text",
            "files"
          ],
          "properties": {
            "text": {
              "type": [
                "string",
                "null"
              ]
            },
            "data": {
              "description": "Parsed JSON when the textual result is JSON."
            },
            "name": {
              "type": "string"
            },
            "mime": {
              "type": "string"
            },
            "files": {
              "type": "array",
              "items": {
                "type": "object",
                "required": [
                  "name",
                  "mime",
                  "bytes",
                  "base64"
                ],
                "properties": {
                  "name": {
                    "type": "string"
                  },
                  "mime": {
                    "type": "string"
                  },
                  "bytes": {
                    "type": "integer"
                  },
                  "base64": {
                    "type": "string",
                    "contentEncoding": "base64"
                  }
                }
              }
            }
          }
        }
      }
    },
    "processing": "Server; same transformation code as browser tools",
    "limits": {
      "request_bytes": 8388608,
      "input_characters": 1000000,
      "files_bytes": 5242880,
      "max_files": 20,
      "timeout_seconds": 12
    }
  },
  "agent_processing": "Server; same transformation code as browser tools",
  "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

Append with header alignment.

Useful next steps

How to use Merge CSV

  1. Choose one or more files in a supported format.
  2. Review the settings, then choose Run Merge CSV.
  3. Review the result, then use Copy result or a download link when available.

Working with merge csv

Spreadsheet tasks involve values, formulas, data types and presentation. A conversion may preserve the displayed value without preserving the formula that produced it. Identifiers, dates and locale-specific decimal separators deserve special attention.

Common questions

Why do identifiers lose leading zeros?

A spreadsheet can interpret a text identifier as a number. Once 00123 is treated as 123, formatting may be needed to display zeros again. Preserve the original value as text when its exact representation matters.

Does CSV keep formulas and multiple sheets?

CSV represents one flat table. It does not retain a workbook’s sheets, formatting or full formula behavior. Treat it as an exchange format for values and review how the receiving application interprets them.

Continue your workflow: Compare CSV, CSV join, CSV pivot.