reindex_graph · Mnemosyne MCP: Risk & Policy

WHAT IT DOES

What reindex_graph does on Mnemosyne MCP

AI agents invoke reindex_graph to trigger actions in Mnemosyne MCP. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why reindex_graph needs a policy

The name suggests rebuilding or regenerating an index for a knowledge graph, which is an operational/execution action rather than a simple read or write. Reindexing typically triggers a background process or job and can have side effects on query performance or availability, but is generally reversible. With no description to confirm, confidence is low and Execute is the most likely category based on the name alone.

From the tool's definition Tool name 'reindex_graph' — description is empty and uninformative.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

reindex_graph Rate-limited

reindex_graph stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "reindex_graph": {
      "limits": [
        {
          "counter": "reindex_graph_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Mnemosyne MCP, so you can run agents against it safely.

FAQ

Questions about reindex_graph

What does the reindex_graph tool do? +

reindex_graph. It is categorised as a Execute tool in the Mnemosyne MCP MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on reindex_graph? +

Register the Mnemosyne MCP server in PolicyLayer and add a rule for reindex_graph: 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 Mnemosyne MCP. Nothing to install.

What risk level is reindex_graph? +

reindex_graph is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit reindex_graph? +

Yes. Add a rate_limit block to the reindex_graph 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.

How do I block reindex_graph completely? +

Set action: deny in the PolicyLayer policy for reindex_graph. 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.

What MCP server provides reindex_graph? +

reindex_graph is provided by the Mnemosyne MCP server (sophia-labs/mnemosyne-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.