AI agents use ga4.custom_dimensions.create to create or update resources in Ads — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Ads environment.
This tool creates a new custom dimension in GA4, which is a Write operation. It modifies configuration data on a GA4 property but is reversible (custom dimensions can be deleted). The dry-run default reduces immediate risk, but misuse could clutter GA4 properties with unwanted dimensions. Severity is medium due to the configuration impact on analytics tracking.
From the tool's definition 'Create a custom dimension on a GA4 property' and 'Dry-run by default' — creates a new resource but is reversible and defaults to safe dry-run mode
Attacks that exploit this kind of access
Create a custom dimension on a GA4 property. Required fields: parameter_name (the tag/event param to source from) and display_name. Defaults scope to EVENT. Dry-run by default. It is categorised as a Write tool in the Ads MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Ads MCP server in PolicyLayer and add a rule for ga4.custom_dimensions.create: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Ads. Nothing to install.
ga4.custom_dimensions.create is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the ga4.custom_dimensions.create rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for ga4.custom_dimensions.create. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
ga4.custom_dimensions.create is provided by the Ads MCP server (manlikemuneeb/ads-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
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