catalog_activate · tin-can MCP: Risk & Policy

WHAT IT DOES

What catalog_activate does on tin-canMCP

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

WHY IT NEEDS A POLICY

Why catalog_activate needs a policy

The tool modifies system state by activating broker groups/tiers in either replace or add modes. 'Replace' suggests overwriting tier configuration, which is reversible (can be undone by activating different tiers), making this Write rather than Destructive.

From the tool's definition Activates broker groups/tiers with modes including 'replace' (default) and 'add', modifying the state of catalog tiers and groups without permanent deletion.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

catalog_activate Rate-limited

catalog_activate 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": {
    "catalog_activate": {
      "limits": [
        {
          "counter": "catalog_activate_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 tin-canMCP, so you can run agents against it safely.

FAQ

Questions about catalog_activate

What does the catalog_activate tool do? +

Activate broker groups/tiers. mode is 'replace' (default) or 'add'. It is categorised as a Write tool in the tin-canMCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on catalog_activate? +

Register the tin-can MCP server in PolicyLayer and add a rule for catalog_activate: 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 tin-canMCP. Nothing to install.

What risk level is catalog_activate? +

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

Can I rate-limit catalog_activate? +

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

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

catalog_activate is provided by the tin-can MCP server (juangrukat/tin-canmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.