Find all instances of specified DEXPI class types in a model. Returns equipment inventory/search results with optional filtering and pagination.
AI agents call search_instances to retrieve information from Engineering MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves and queries data from process engineering diagrams without creating, modifying, deleting, or executing any operations. It is purely informational—searching for and returning inventory of equipment instances with filtering capabilities. This is a classic Read operation with minimal risk profile.
From the tool's definition Tool description states it "Find[s] all instances" and "Returns equipment inventory/search results with optional filtering and pagination." The verb 'search' and 'find' combined with 'returns results' indicates a query operation with no modification.
Documented attack patterns abuse exactly the kind of access search_instances gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Engineering MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for search_instances:
{
"version": "1",
"default": "deny",
"tools": {
"search_instances": {}
}
}search_instances 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 all instances of specified DEXPI class types in a model. Returns equipment inventory/search results with optional filtering and pagination. It is categorised as a Read tool in the Engineering MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Engineering MCP Server MCP server in PolicyLayer and add a rule for search_instances: 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 Engineering MCP Server. Nothing to install.
search_instances 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 search_instances 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 search_instances. 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.
search_instances is provided by the Engineering MCP Server MCP server (puran-water/dexpi-sfiles-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Engineering MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
72 Engineering MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.