Get statistics and health metrics for the knowledge base index. Read-only. No side effects. Returns: JSON string with system metrics: total documents, total chunks, embedding model name, BM25 status, query cache hit rate, and file watcher status. Usage: Use for system health checks — verifying th...
AI agents call get_index_stats to retrieve information from Knowledge Rag without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool only retrieves and reports existing metrics about the knowledge base index state. It performs no modifications, deletions, executions, or side effects. The explicit statement 'Read-only. No side effects' combined with the sole purpose of returning diagnostic statistics places it squarely in the Read category with low severity.
From the tool's definition Tool description explicitly states "Read-only. No side effects." Returns JSON metrics about index statistics (total documents, chunks, embedding model name, BM25 status, query cache hit rate, file watcher status). Pure retrieval of system health information.
Documented attack patterns abuse exactly the kind of access get_index_stats gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Knowledge Rag, and nothing reaches the server without passing your rules. This is the rule we recommend for get_index_stats:
{
"version": "1",
"default": "deny",
"tools": {
"get_index_stats": {}
}
}get_index_stats 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.
Get statistics and health metrics for the knowledge base index. Read-only. No side effects. Returns: JSON string with system metrics: total documents, total chunks, embedding model name, BM25 status, query cache hit rate, and file watcher status. Usage: Use for system health checks — verifying the embedding model loaded, checking index population, or monitoring cache efficiency. Use list_categories() for per-category document counts instead. Use evaluate_retrieval() to measure actual search quality with test queries. It is categorised as a Read tool in the Knowledge Rag MCP Server, which means it retrieves data without modifying state.
Register the Knowledge Rag MCP server in PolicyLayer and add a rule for get_index_stats: 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 Knowledge Rag. Nothing to install.
get_index_stats 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 get_index_stats 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 get_index_stats. 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.
get_index_stats is provided by the Knowledge Rag MCP server (lyonzin/knowledge-rag). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Knowledge Rag, 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.
12 Knowledge Rag tools catalogued and risk-classified — across an index of 43,000+ MCP servers.