# AttachmentDescriptor

> Tracon documentation. Tracon is a .NET package family that adds a control
> plane on Microsoft Agent Framework, published as NuGet packages that run
> inside your own ASP.NET Core application.
>
> Page: https://tracon.dev/http-api/schemas/attachmentdescriptor/
> Summary: OpenAPI request or response schema for AttachmentDescriptor, including required fields, defaults, constraints, and linked nested types.

[← All HTTP schemas](/http-api/schemas/)

The metadata of an uploaded attachment.

**Shape:** `object`

| Property | Required | Type | Description | Rules |
|---|---|---|---|---|
| `id` | yes | `string (uuid)` | Gets the attachment id. | — |
| `tenantId` | yes | `string` | Gets the tenant the attachment belongs to. | — |
| `sessionId` | no | `string` | Gets the session the attachment was uploaded to. `null` for an upload without a session. | — |
| `runId` | no | `string (uuid)` | Gets the run that produced the attachment. `null` for a user upload. | — |
| `fileName` | yes | `string` | Gets the original file name. | — |
| `mediaType` | yes | `string` | Gets the validated MIME type. It is the result of the magic-byte check, not the `Content-Type` the client sent. | — |
| `byteSize` | yes | `integer (int64)` | Gets the size of the content in bytes. | pattern `^-?(?:0\\|[1-9]\d*)$` |
| `sha256` | yes | `string` | Gets the SHA-256 digest of the content (hexadecimal, upper case). | — |
| `createdBy` | no | `string` | Gets the actor that uploaded it, or `null` when it is unknown. | — |
| `createdAt` | yes | `string (date-time)` | Gets the upload time. | — |