# custom_update_email_variable

[CUSTOM] Calls the Marketo REST API directly (not Adobe's native MCP).

Agent View of the PolicyLayer registry record for `custom_update_email_variable`. HTML page: https://policylayer.com/tools/tyron-pretorius-marketo-mcp/custom-update-email-variable

## Facts

- Tool: `custom_update_email_variable`
- 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_update_email_variable",
    "arguments": {}
  }
}
```

## Why custom_update_email_variable is rated Medium

This tool creates or modifies email variables in Marketo—a reversible Write operation. Severity is high (not critical) because email variable changes could affect marketing campaigns reaching many contacts, but are not financial transactions or irreversible deletions.

From the tool's own definition: "Tool name contains 'update' and description indicates it 'Calls the Marketo REST API directly' to modify email variables."

## Use case

AI agents use custom_update_email_variable 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_update_email_variable": {
      "limits": [
        {
          "counter": "custom_update_email_variable_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