# download-bytes

Download binary content from Microsoft Graph and return it as base64. Single tool for any binary read: drive file content, mail attachment, profile photo, Teams hosted content, meeting recording. Returns { contentType, encoding: "base64", contentLength, contentBytes }. For large drive/SharePoint file content, prefer get-download-url, which returns a pre-authenticated URL to stream bytes out-of-band instead of base64 through the agent context.

Agent View of the PolicyLayer registry record for `download-bytes`. HTML page: https://policylayer.com/tools/jo3zik-ms-365-mcp-server/download-bytes

## Facts

- Tool: `download-bytes`
- Server: Ms 365 (`@jo3zik/ms-365-mcp-server`) — https://policylayer.com/tools/jo3zik-ms-365-mcp-server.md
- Install: `npx -y @jo3zik/ms-365-mcp-server`
- Homepage: https://www.npmjs.com/package/@jo3zik/ms-365-mcp-server
- Risk category: Read (Low risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 1 (1 required)
- Recommended policy verdict: Allowed

## Parameters

| Parameter | Type | Required | Description |
| --- | --- | --- | --- |
| `target` | string | yes | Relative Microsoft Graph path starting with "/". Common paths: /drives/{drive-id}/items/{driveItem-id}/content (drive file content); /me/messages/{message-id}/a |

Parameters from the server's own tool schema.

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "download-bytes",
    "arguments": {
      "target": "<target>"
    }
  }
}
```

## Why download-bytes is rated Low

Even though download-bytes only reads data, uncontrolled read access leaks sensitive information and racks up API costs: an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.

## Use case

AI agents call download-bytes to retrieve information from Ms 365 without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

Verdict: **Allowed**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Ms 365:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "download-bytes": {}
  }
}
```

## Other tools on Ms 365 (193)

- `cancel-calendar-event` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/cancel-calendar-event.md
- `clear-excel-range` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/clear-excel-range.md
- `delete-calendar` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-calendar.md
- `delete-calendar-event` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-calendar-event.md
- `delete-contact-folder` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-contact-folder.md
- `delete-drive-item-permission` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-drive-item-permission.md
- `delete-excel-range` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-excel-range.md
- `delete-excel-table-row` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-excel-table-row.md
- `delete-focused-inbox-override` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-focused-inbox-override.md
- `delete-mail-attachment` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-mail-attachment.md
- `delete-mail-folder` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-mail-folder.md
- `delete-mail-message` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-mail-message.md
- `delete-mail-rule` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-mail-rule.md
- `delete-my-calendar-permission` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-my-calendar-permission.md
- `delete-onedrive-file` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-onedrive-file.md
- `delete-onenote-page` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-onenote-page.md
- `delete-outlook-contact` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-outlook-contact.md
- `delete-planner-bucket` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-planner-bucket.md
- `delete-planner-task-message` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-planner-task-message.md
- `delete-specific-calendar-event` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-specific-calendar-event.md
- `delete-subscription` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-subscription.md
- `delete-todo-linked-resource` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-todo-linked-resource.md
- `delete-todo-task` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-todo-task.md
- `delete-todo-task-list` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/delete-todo-task-list.md
- `graph-batch` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/graph-batch.md
- `logout` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/logout.md
- `remove-account` — Destructive — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/remove-account.md
- `parse-teams-url` — Execute — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/parse-teams-url.md
- `tentatively-accept-calendar-event` — Execute — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/tentatively-accept-calendar-event.md
- `dismiss-calendar-event-reminder` — Read — https://policylayer.com/tools/jo3zik-ms-365-mcp-server/dismiss-calendar-event-reminder.md
- …and 163 more: https://policylayer.com/tools/jo3zik-ms-365-mcp-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=jo3zik-ms-365-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/jo3zik-ms-365-mcp-server