Find every place in a PDF where a signature, initials, or date should go. Returns a typed list of zones with coordinates (top-left origin, points). Use this BEFORE apply_signature — never guess coordinates, always apply at a returned zone. Detection layers: (1) AcroForm signature fields (confiden...
AI agents call detect_signature_zones 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.
detect_signature_zones reads PDF metadata and AcroForm field structures to identify signature locations and return coordinate data. It has no side effects, does not modify the PDF, does not execute code, and does not trigger external operations.
From the tool's definition Tool performs detection and analysis only: 'Find every place in a PDF where a signature, initials, or date should go.
Risk signalsBulk/mass operation — affects multiple targets
Documented attack patterns abuse exactly the kind of access detect_signature_zones 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 detect_signature_zones:
{
"version": "1",
"default": "deny",
"tools": {
"detect_signature_zones": {}
}
}detect_signature_zones 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.
Find every place in a PDF where a signature, initials, or date should go. Returns a typed list of zones with coordinates (top-left origin, points). Use this BEFORE apply_signature — never guess coordinates, always apply at a returned zone. Detection layers: (1) AcroForm signature fields (confidence 0.99), (2) AcroForm fields named. 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 detect_signature_zones: 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.
detect_signature_zones 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 detect_signature_zones 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 detect_signature_zones. 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.
detect_signature_zones 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.