update_stock · MCPDischarge MCP: Risk & Policy

WHAT IT DOES

What update_stock does on MCPDischarge

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

WHY IT NEEDS A POLICY

Why update_stock needs a policy

This tool creates or modifies inventory data reversibly (stock levels can be adjusted up or down). While it affects pharmaceutical supply chain operations in a hospital setting, the modifications are not permanently destructive and can be corrected by subsequent adjustments.

From the tool's definition Tool description states 'Adjust inventory level for a drug (add or remove units)' - explicitly modifies data by adding or removing stock quantities.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_stock Rate-limited

update_stock 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": {
    "update_stock": {
      "limits": [
        {
          "counter": "update_stock_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 MCPDischarge, so you can run agents against it safely.

FAQ

Questions about update_stock

What does the update_stock tool do? +

Adjust inventory level for a drug (add or remove units). It is categorised as a Write tool in the MCPDischarge MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on update_stock? +

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

What risk level is update_stock? +

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

Can I rate-limit update_stock? +

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

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

update_stock is provided by the MCPDischarge MCP server (prashantsingh1234/mcp_project). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.