Find instances of a class. Returns instance IRIs with labels.
AI agents call find_instances to retrieve information from RDF4J 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 lists instances matching a class from an RDF knowledge graph. It performs a lookup/search operation analogous to 'list' or 'fetch' with no capability to modify, execute external code, or cause destructive changes. The sibling tools (describe_resource, get_statistics, search_classes, search_properties, sparql_ask) all indicate a read-only query environment.
From the tool's definition Tool description states 'Find instances of a class. Returns instance IRIs with labels.' The verb 'Returns' and the read-only nature of retrieving IRIs and labels indicate a query operation with no data modification or side effects.
Attacks that exploit this kind of access
Find instances of a class. Returns instance IRIs with labels. It is categorised as a Read tool in the RDF4J MCP Server MCP Server, which means it retrieves data without modifying state.
Register the RDF4J MCP Server MCP server in PolicyLayer and add a rule for find_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 RDF4J MCP Server. Nothing to install.
find_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 find_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 find_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.
find_instances is provided by the RDF4J MCP Server MCP server (odysa/rdf4j-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →