steam_grantInventoryItem · Steam MCP Server MCP

WHAT IT DOES

What steam_grantInventoryItem does on Steam MCP Server

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

WHY IT NEEDS A POLICY

Why steam_grantInventoryItem needs a policy

This tool creates a new inventory item for a player, which is a Write operation (creating data). While it could have financial implications if items have real-world value, it is not directly moving money. However, granting items to players can have significant economic impact in games with trading economies, and requires elevated partner API credentials.

From the tool's definition Grant an inventory item to a player via the partner API. Intended for dev/test or server-side rewards.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

steam_grantInventoryItem Rate-limited

steam_grantInventoryItem 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": {
    "steam_grantInventoryItem": {
      "limits": [
        {
          "counter": "steam_grantinventoryitem_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 Steam MCP Server, so you can run agents against it safely.

FAQ

Questions about steam_grantInventoryItem

What does the steam_grantInventoryItem tool do? +

Grant an inventory item to a player via the partner API. Intended for dev/test or server-side rewards. Requires a publisher API key with server IP allowlisted in Steamworks partner settings. It is categorised as a Write tool in the Steam MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on steam_grantInventoryItem? +

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

What risk level is steam_grantInventoryItem? +

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

Can I rate-limit steam_grantInventoryItem? +

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

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

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