attachmentItem

{
  "$schema": "https://json-schema.org/draft/2020-12/schema",
  "$id": "https://artifacts.apis.io/microsoft-365/json-schema/microsoft-365-microsoft-graph-attachment-item-schema.json",
  "title": "attachmentItem",
  "x-generated": "2026-11-04",
  "x-method": "derived",
  "x-generator": "derive-json-schema.py",
  "x-source": "openapi/microsoft-365-mail-api-openapi.yml#/components/schemas/microsoft.graph.attachmentItem",
  "type": "object",
  "properties": {
    "attachmentType": {
      "$ref": "#/$defs/microsoft.graph.attachmentType"
    },
    "contentId": {
      "type": [
        "string",
        "null"
      ],
      "description": "The CID or Content-Id of the attachment for referencing for the in-line attachments using the <img src='cid:contentId'> tag in HTML messages. Optional."
    },
    "contentType": {
      "type": [
        "string",
        "null"
      ],
      "description": "The nature of the data in the attachment. Optional."
    },
    "isInline": {
      "type": [
        "boolean",
        "null"
      ],
      "description": "true if the attachment is an inline attachment; otherwise, false. Optional."
    },
    "name": {
      "type": [
        "string",
        "null"
      ],
      "description": "The display name of the attachment. This can be a descriptive string and doesn't have to be the actual file name. Required."
    },
    "size": {
      "type": [
        "number",
        "null"
      ],
      "description": "The length of the attachment in bytes. Required.",
      "format": "int64"
    }
  },
  "additionalProperties": {
    "type": "object"
  },
  "$defs": {
    "microsoft.graph.attachmentType": {
      "title": "attachmentType",
      "enum": [
        "file",
        "item",
        "reference"
      ],
      "type": "string"
    }
  }
}