replace_constant_with_distribution

WHAT IT DOES

What replace_constant_with_distribution does on ModelRisk MCP

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

WHY IT NEEDS A POLICY

Why replace_constant_with_distribution needs a policy

This tool modifies workbook content by replacing hardcoded values with probability distributions—a reversible write operation. It does not delete data (not Destructive), execute arbitrary code (not Execute), or involve financial transactions (not Financial). The empty description reduces confidence slightly, but the function name and context clearly indicate data modification within a risk modeling workbook.

From the tool's definition Tool name 'replace_constant_with_distribution' indicates modification of spreadsheet data by substituting values. Sibling tools like 'get_cell' and 'get_workbook_summary' confirm this operates within Excel workbooks.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

replace_constant_with_distribution Rate-limited

replace_constant_with_distribution 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "replace_constant_with_distribution": {
      "limits": [
        {
          "counter": "replace_constant_with_distribution_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches ModelRisk MCP, so you can run agents against it safely.

FAQ

Questions about replace_constant_with_distribution

What does the replace_constant_with_distribution tool do? +

replace_constant_with_distribution. It is categorised as a Write tool in the ModelRisk MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on replace_constant_with_distribution? +

Register the ModelRisk MCP server in PolicyLayer and add a rule for replace_constant_with_distribution: 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 ModelRisk MCP. Nothing to install.

What risk level is replace_constant_with_distribution? +

replace_constant_with_distribution is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit replace_constant_with_distribution? +

Yes. Add a rate_limit block to the replace_constant_with_distribution 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 replace_constant_with_distribution completely? +

Set action: deny in the PolicyLayer policy for replace_constant_with_distribution. 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 replace_constant_with_distribution? +

replace_constant_with_distribution is provided by the ModelRisk MCP server (vosesoftware/modelrisk-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.