This record as markdown: /tools/easehee-rhino-mcp/rhino-viewport-preview.md
What rhino_viewport_preview does on Rhino
AI agents use rhino_viewport_preview to create or update resources in Rhino, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Rhino environment.
Why rhino_viewport_preview is rated Medium
An AI agent can call rhino_viewport_preview faster than any human can review: one bad instruction and it creates or modifies resources in Rhino by the hundred, each call as confident as the last.
Attacks that exploit this kind of access
The rule that runs rhino_viewport_preview safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Rhino, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For rhino_viewport_preview, this is the rule to start with:
rhino_viewport_preview stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Rhino, apply this rule, and every rhino_viewport_preview call is checked against it from then on.
Questions about rhino_viewport_preview
rhino_viewport_preview is a write tool on the Rhino MCP server. It is categorised as a Write tool in the Rhino MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Rhino MCP server in PolicyLayer and add a rule for rhino_viewport_preview: 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 Rhino. Nothing to install.
rhino_viewport_preview 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 rhino_viewport_preview 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 rhino_viewport_preview. 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.
rhino_viewport_preview is provided by the Rhino MCP server (easehee/rhino-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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