physics_set_material · Flex Sensor Agent MCP: Risk & Policy

WHAT IT DOES

What physics_set_material does on Flex Sensor Agent

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

WHY IT NEEDS A POLICY

Why physics_set_material needs a policy

This tool writes/modifies material properties in an active COMSOL simulation, which affects subsequent calculations and results. While reversible (can be re-set), it has high blast radius if an AI agent applies incorrect material values, potentially invalidating the entire simulation analysis.

From the tool's definition Tool name 'physics_set_material' indicates modification of material properties in a physics simulation context (COMSOL Multiphysics). The 'set' verb clearly denotes a write operation that creates or modifies simulation parameters.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

physics_set_material Rate-limited

physics_set_material 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": {
    "physics_set_material": {
      "limits": [
        {
          "counter": "physics_set_material_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

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

FAQ

Questions about physics_set_material

What does the physics_set_material tool do? +

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

How do I enforce a policy on physics_set_material? +

Register the Flex Sensor Agent MCP server in PolicyLayer and add a rule for physics_set_material: 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 Flex Sensor Agent. Nothing to install.

What risk level is physics_set_material? +

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

Can I rate-limit physics_set_material? +

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

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

physics_set_material is provided by the Flex Sensor Agent MCP server (tonghui666/flex-sensor-agent-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.