# custom_upload_file

A write tool on the Marketo MCP Server MCP server.

Agent View of the PolicyLayer registry record for `custom_upload_file`. HTML page: https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-upload-file

## Facts

- Tool: `custom_upload_file`
- Server: Marketo MCP Server (`tyron-pretorius/marketo-mcp`) — https://policylayer.com/tools/tyron-pretorius-marketo-mcp.md
- Homepage: https://github.com/tyron-pretorius/marketo-mcp
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

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

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "custom_upload_file",
    "arguments": {}
  }
}
```

## Why custom_upload_file is rated Medium

The name implies a file upload operation, which is a Write action. However, the empty description significantly lowers confidence. Given the Marketo context (marketing assets like emails, images), this likely uploads files to Marketo's file storage. Severity is high because an AI agent could upload malicious or unintended content at scale.

From the tool's own definition: "Tool name 'custom_upload_file' suggests uploading/writing file data; description is empty and uninformative."

## Use case

AI agents use custom_upload_file to create or update resources in Marketo MCP Server, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Marketo MCP Server environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Marketo MCP Server:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "custom_upload_file": {
      "limits": [
        {
          "counter": "custom_upload_file_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Marketo MCP Server (297)

- `custom_cancel_lead_export_job` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-cancel-lead-export-job.md
- `custom_delete_companies` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-companies.md
- `custom_delete_custom_activity_type` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-custom-activity-type.md
- `custom_delete_custom_activity_type_attributes` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-custom-activity-type-attributes.md
- `custom_delete_custom_object_type` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-custom-object-type.md
- `custom_delete_custom_object_type_fields` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-custom-object-type-fields.md
- `custom_delete_custom_objects` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-custom-objects.md
- `custom_delete_email` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-email.md
- `custom_delete_email_module` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-email-module.md
- `custom_delete_email_template` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-email-template.md
- `custom_delete_email_template2` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-email-template2.md
- `custom_delete_email2` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-email2.md
- `custom_delete_folder` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-folder.md
- `custom_delete_form` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-form.md
- `custom_delete_form_field` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-form-field.md
- `custom_delete_form_fieldset_field` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-form-fieldset-field.md
- `custom_delete_fragment` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-fragment.md
- `custom_delete_landing_page` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-landing-page.md
- `custom_delete_landing_page_content_section` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-landing-page-content-section.md
- `custom_delete_landing_page_template` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-landing-page-template.md
- `custom_delete_leads` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-leads.md
- `custom_delete_named_account_lists` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-named-account-lists.md
- `custom_delete_named_accounts` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-named-accounts.md
- `custom_delete_opportunities` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-opportunities.md
- `custom_delete_opportunity_roles` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-opportunity-roles.md
- `custom_delete_program` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-program.md
- `custom_delete_program_members` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-program-members.md
- `custom_delete_redirect_rule` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-redirect-rule.md
- `custom_delete_sales_persons` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-sales-persons.md
- `custom_delete_smart_campaign` — Destructive — https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-delete-smart-campaign.md
- …and 267 more: https://policylayer.com/tools/tyron-pretorius-marketo-mcp.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=tyron-pretorius-marketo-mcp · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/tyron-pretorius-marketo-mcp