use_skill · Tenzro Ledger MCP: Risk & Policy

WHAT IT DOES

What use_skill does on Tenzro Ledger MCP

AI agents invoke use_skill to trigger actions in Tenzro Ledger MCP. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why use_skill needs a policy

This tool executes code-like operations (skills) triggered by user-supplied inputs. While not explicitly destructive or financial, the Execute category applies because: (1) it invokes external operations, (2) effects depend on what skill is registered and what input data is provided, (3) on a platform supporting wallets, payments, and agents, a skill invocation could trigger significant side effects. Confidence is 0.

From the tool's definition Tool description states 'Invoke a registered skill with the given input data.' The word 'invoke' combined with 'skill' on a ledger/payments/agents platform indicates execution of potentially arbitrary operations.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

use_skill Rate-limited

use_skill stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "use_skill": {
      "limits": [
        {
          "counter": "use_skill_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about use_skill

What does the use_skill tool do? +

Invoke a registered skill with the given input data. It is categorised as a Execute tool in the Tenzro Ledger MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on use_skill? +

Register the Tenzro Ledger MCP server in PolicyLayer and add a rule for use_skill: 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 Tenzro Ledger MCP. Nothing to install.

What risk level is use_skill? +

use_skill is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit use_skill? +

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

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

use_skill is provided by the Tenzro Ledger MCP server (https://canton-mcp.tenzro.network/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.