store.vector-upsert · MCP: Risk & Policy

WHAT IT DOES

What store.vector-upsert does on Mcp

AI agents use store.vector-upsert to create or update resources in Mcp — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mcp environment.

WHY IT NEEDS A POLICY

Why store.vector-upsert needs a policy

This tool performs a Write operation—it modifies data (creating or updating vectors in storage) in a reversible manner. It does not delete data (ruling out Destructive), does not execute arbitrary commands (Execute), does not move money (Financial), and is not a simple read (Read).

From the tool's definition Tool description uses 'upsert' (update/insert operation) to modify vector storage. 'Upsert' is a reversible write operation that creates or modifies data records in a vector database.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

store.vector-upsert Rate-limited

store.vector-upsert stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "store.vector-upsert": {
      "limits": [
        {
          "counter": "store.vector-upsert_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about store.vector-upsert

What does the store.vector-upsert tool do? +

STORE: upsert a vector for semantic retrieval, scoped to. It is categorised as a Write tool in the Mcp MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on store.vector-upsert? +

Register the MCP server in PolicyLayer and add a rule for store.vector-upsert: 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 Mcp. Nothing to install.

What risk level is store.vector-upsert? +

store.vector-upsert is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit store.vector-upsert? +

Yes. Add a rate_limit block to the store.vector-upsert 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 store.vector-upsert completely? +

Set action: deny in the PolicyLayer policy for store.vector-upsert. 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 store.vector-upsert? +

store.vector-upsert is provided by the MCP server (@2sio/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.