# Start a document upload

> The start_document_upload MCP tool: start a document upload.

`start_document_upload` · writes

[REST: `POST /v1/trips/{tripId}/documents`](https://api.bymundi.com/docs/reference/documents.startUpload.md)

## What the model reads

Reserves a document on a trip and returns a single-use upload URL (valid 2 hours) and a ready `curl` command. Only useful if you can run shell commands (e.g. Claude Code): PUT the file's bytes to the URL with exactly the returned headers, then call complete_document_upload. For a small file you write yourself use upload_document; for a file on the user's computer use upload_file when it is offered. An unfinished upload is removed after 24 hours.

Permissions: documents:write.
This cannot be undone.

## Input

| Field | Type | Required | Description |
|---|---|---|---|
| `tripId` | uuid | yes |  |
| `name` | string | yes | The name shown in bymundi, with its extension (e.g. 'Kyoto hotel voucher.pdf'). max 200 chars |
| `mimeType` | "application/pdf" \| "image/png" \| "image/jpeg" \| "image/webp" \| "image/gif" \| "application/msword" \| "application/vnd.openxmlformats-officedocument.wordprocessingml.document" \| "application/vnd.ms-excel" \| "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" \| "application/vnd.ms-powerpoint" \| "application/vnd.openxmlformats-officedocument.presentationml.presentation" \| "text/plain" \| "text/csv" \| "application/zip" | yes | The file's type — only these are accepted. |
| `byteSize` | integer | yes | The file's size in bytes (at most 5 MB). 1–5242880 |

## Input schema (JSON)

```json
{
  "type": "object",
  "properties": {
    "tripId": {
      "type": "string",
      "format": "uuid"
    },
    "name": {
      "type": "string",
      "minLength": 1,
      "maxLength": 200,
      "description": "The name shown in bymundi, with its extension (e.g. 'Kyoto hotel voucher.pdf')."
    },
    "mimeType": {
      "type": "string",
      "enum": [
        "application/pdf",
        "image/png",
        "image/jpeg",
        "image/webp",
        "image/gif",
        "application/msword",
        "application/vnd.openxmlformats-officedocument.wordprocessingml.document",
        "application/vnd.ms-excel",
        "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet",
        "application/vnd.ms-powerpoint",
        "application/vnd.openxmlformats-officedocument.presentationml.presentation",
        "text/plain",
        "text/csv",
        "application/zip"
      ],
      "description": "The file's type — only these are accepted."
    },
    "byteSize": {
      "type": "integer",
      "minimum": 1,
      "maximum": 5242880,
      "description": "The file's size in bytes (at most 5 MB)."
    }
  },
  "required": [
    "tripId",
    "name",
    "mimeType",
    "byteSize"
  ],
  "additionalProperties": false
}
```