List all saved signatures in ~/.pdf-toolkit-files/signatures/. Returns each signature
AI agents call list_signatures to retrieve information from PDF Tools without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves and enumerates existing signature data from a local directory without modifying, deleting, or executing any operations. It is a straightforward information retrieval function with minimal blast radius if misused by an AI agent.
From the tool's definition Tool name 'list_signatures' and description 'List all saved signatures' indicate a query/retrieval operation with no side effects. The verb 'List' and 'Returns' confirm read-only behavior.
Documented attack patterns abuse exactly the kind of access list_signatures gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and PDF Tools, and nothing reaches the server without passing your rules. This is the rule we recommend for list_signatures:
{
"version": "1",
"default": "deny",
"tools": {
"list_signatures": {}
}
}list_signatures is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
Free to start. No card required.
List all saved signatures in ~/.pdf-toolkit-files/signatures/. Returns each signature. It is categorised as a Read tool in the PDF Tools MCP Server, which means it retrieves data without modifying state.
Register the PDF Tools MCP server in PolicyLayer and add a rule for list_signatures: 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 PDF Tools. Nothing to install.
list_signatures 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 list_signatures 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 list_signatures. 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.
list_signatures is provided by the PDF Tools MCP server (open-document-alliance/pdf-tools). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 36 PDF Tools tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
36 PDF Tools tools catalogued and risk-classified — across an index of 42,500+ MCP servers.