Look up historical security risk grades for an MCP server from the public ToolTrust Directory. Accepts the kebab-case name of the server and returns its full JSON scan report, or 404 if not found.
Part of the ToolTrust Scanner server.
Free to start. No card required.
AI agents call tooltrust_lookup to retrieve information from ToolTrust Scanner without modifying any data. This is common in research, monitoring, and reporting workflows where the agent needs context before taking action. Because read operations don't change state, they are generally safe to allow without restrictions -- but you may still want rate limits to control API costs.
Even though tooltrust_lookup only reads data, uncontrolled read access can leak sensitive information or rack up API costs. An agent caught in a retry loop could make thousands of calls per minute. A rate limit gives you a safety net without blocking legitimate use.
Read-only tools are safe to allow by default. No rate limit needed unless you want to control costs.
{
"version": "1",
"default": "deny",
"tools": {
"tooltrust_lookup": {}
}
}See the full ToolTrust Scanner policy for all 5 tools.
These attack patterns abuse exactly the kind of access tooltrust_lookup gives an agent. Each links to the full case and the policy that stops it:
Other read tools across the catalogue. The same approach applies to each: allow, with a rate cap to control cost.
Look up historical security risk grades for an MCP server from the public ToolTrust Directory. Accepts the kebab-case name of the server and returns its full JSON scan report, or 404 if not found.. It is categorised as a Read tool in the ToolTrust Scanner MCP Server, which means it retrieves data without modifying state.
Register the ToolTrust Scanner MCP server in PolicyLayer and add a rule for tooltrust_lookup: 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 ToolTrust Scanner. Nothing to install.
tooltrust_lookup is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the tooltrust_lookup 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.
Set action: deny in the PolicyLayer policy for tooltrust_lookup. 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.
tooltrust_lookup is provided by the ToolTrust Scanner MCP server (tooltrust-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 5 ToolTrust Scanner tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
4,600+ MCP servers and 31,000+ tools scanned and risk-classified.