index_now · MemoryMesh MCP: Risk & Policy

WHAT IT DOES

What index_now does on MemoryMesh

AI agents invoke index_now to trigger actions in MemoryMesh. 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 index_now needs a policy

This tool executes a side-effecting operation (indexing) that modifies the internal state of the MemoryMesh system by processing files and updating indices. While not destructive (indices can be regenerated) or financial, it is an active operation that triggers external processing.

From the tool's definition Tool description states 'Trigger an immediate (re-)index of a file, directory, or all sources.' The verb 'trigger' combined with 'immediate (re-)index' indicates execution of an indexing operation whose effects depend on the file/directory argument provided.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

index_now Rate-limited

index_now 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": {
    "index_now": {
      "limits": [
        {
          "counter": "index_now_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 MemoryMesh, so you can run agents against it safely.

FAQ

Questions about index_now

What does the index_now tool do? +

Trigger an immediate (re-)index of a file, directory, or all sources. It is categorised as a Execute tool in the MemoryMesh MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on index_now? +

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

What risk level is index_now? +

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

Can I rate-limit index_now? +

Yes. Add a rate_limit block to the index_now 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 index_now completely? +

Set action: deny in the PolicyLayer policy for index_now. 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 index_now? +

index_now is provided by the MemoryMesh MCP server (kilhubprojects/memory-mesh). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.