Low Risk

plot_hypervolume_history

Return the hypervolume history plot as an image.

How to control plot_hypervolume_history ↓

AI agents call plot_hypervolume_history to retrieve information from Optuna MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

Low Risk

This tool retrieves and returns visualization data (a plot image) of existing hypervolume history from an optimization study. It performs a query-like operation that reads data without creating, modifying, deleting, or executing external operations. The tool is informational and analytical in nature, consistent with the Read category for data retrieval operations.

From the tool's definition Tool name 'plot_hypervolume_history' and description 'Return the hypervolume history plot as an image' indicate data retrieval and visualization with no modification of state or side effects.

Documented attack patterns abuse exactly the kind of access plot_hypervolume_history gives an agent:

PolicyLayer is an MCP gateway — it sits between your AI agents and Optuna MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for plot_hypervolume_history:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "plot_hypervolume_history": {}
  }
}

plot_hypervolume_history is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

  1. Create a free account and register Optuna MCP Server — nothing to install.
  2. Add this policy — paste it, or build it visually.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
CAP THIS TOOL →

Free to start. No card required.

Go deeper

What does the plot_hypervolume_history tool do? +

Return the hypervolume history plot as an image. It is categorised as a Read tool in the Optuna MCP Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on plot_hypervolume_history? +

Register the Optuna MCP Server MCP server in PolicyLayer and add a rule for plot_hypervolume_history: 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 Optuna MCP Server. Nothing to install.

What risk level is plot_hypervolume_history? +

plot_hypervolume_history is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit plot_hypervolume_history? +

Yes. Add a rate_limit block to the plot_hypervolume_history 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.

How do I block plot_hypervolume_history completely? +

Set action: deny in the PolicyLayer policy for plot_hypervolume_history. 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.

What MCP server provides plot_hypervolume_history? +

plot_hypervolume_history is provided by the Optuna MCP Server MCP server (optuna/optuna-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Optuna MCP Server tool call.

Deterministic rules across all 26 Optuna MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.

Free to start. No card required.

26 Optuna MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.

// GET IN TOUCH

Have a question or want to learn more? Send us a message.

Message sent.

We'll get back to you soon.