High Risk →

call_tool

Invoke any tool on the SettleGrid marketplace by its slug. Pass arguments as a JSON object. Free showcase tools work without an API key. Paid tools route through the Smart Proxy and require an API key (passed via the x-api-key header on the MCP connection). Use search_tools or list_marketplace_to...

Part of the Settlegrid Discovery MCP server. Enforce policies on this tool with Intercept, the open-source MCP proxy.

AI agents invoke call_tool to trigger processes or run actions in Settlegrid Discovery. Execute operations can have side effects beyond the immediate call -- triggering builds, sending notifications, or starting workflows. Rate limits and argument validation are essential to prevent runaway execution.

call_tool can trigger processes with real-world consequences. An uncontrolled agent might start dozens of builds, send mass notifications, or kick off expensive compute jobs. Intercept enforces rate limits and validates arguments to keep execution within safe bounds.

Execute tools trigger processes. Rate-limit and validate arguments to prevent unintended side effects.

settlegrid-settlegrid-discovery.yaml
tools:
  call_tool:
    rules:
      - action: allow
        rate_limit:
          max: 10
          window: 60
        validate:
          required_args: true

See the full Settlegrid Discovery policy for all 6 tools.

Tool Name call_tool
Category Execute
Risk Level High

Agents calling execute-class tools like call_tool have been implicated in these attack patterns. Read the full case and prevention policy for each:

Browse the full MCP Attack Database →

Other tools in the Execute risk category across the catalogue. The same policy patterns (rate-limit, validate) apply to each.

call_tool is one of the high-risk operations in Settlegrid Discovery. For the full severity-focused view — only the high-risk tools with their recommended policies — see the breakdown for this server, or browse all high-risk tools across every MCP server.

What does the call_tool tool do? +

Invoke any tool on the SettleGrid marketplace by its slug. Pass arguments as a JSON object. Free showcase tools work without an API key. Paid tools route through the Smart Proxy and require an API key (passed via the x-api-key header on the MCP connection). Use search_tools or list_marketplace_tools first to find the right tool and its slug.. It is categorised as a Execute tool in the Settlegrid Discovery MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on call_tool? +

Add a rule in your Intercept YAML policy under the tools section for call_tool. You can allow, deny, rate-limit, or validate arguments. Then run Intercept as a proxy in front of the Settlegrid Discovery MCP server.

What risk level is call_tool? +

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

Can I rate-limit call_tool? +

Yes. Add a rate_limit block to the call_tool rule in your Intercept 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 call_tool completely? +

Set action: deny in the Intercept policy for call_tool. 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 call_tool? +

call_tool is provided by the Settlegrid Discovery MCP server (settlegrid/settlegrid-discovery). Intercept sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policies on Settlegrid Discovery

Open source. One binary. Zero dependencies.

npx -y @policylayer/intercept
github.com/policylayer/intercept →
// GET IN TOUCH

Have a question or want to learn more? Send us a message.

Message sent.

We'll get back to you soon.