vault_update · Connect MCP: Risk & Policy

WHAT IT DOES

What vault_update does on Connect MCP

AI agents use vault_update to create or update resources in Connect MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Connect MCP environment.

WHY IT NEEDS A POLICY

Why vault_update needs a policy

This tool modifies existing data (file content) reversibly. It is Write rather than Destructive because the original content could theoretically be recovered from Obsidian's version history or undo functionality, and the operation itself is not inherently irreversible. An AI agent with access could inadvertently overwrite important notes, but damage is recoverable.

From the tool's definition Tool name 'vault_update' and description 'Replace entire file content' indicate modification of existing files.

Risk signalsBulk/mass operation — affects multiple targets

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vault_update Rate-limited

vault_update 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": {
    "vault_update": {
      "limits": [
        {
          "counter": "vault_update_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 Connect MCP, so you can run agents against it safely.

FAQ

Questions about vault_update

What does the vault_update tool do? +

Replace entire file content. It is categorised as a Write tool in the Connect 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 vault_update? +

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

What risk level is vault_update? +

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

Can I rate-limit vault_update? +

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

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

vault_update is provided by the Connect MCP server (joch/obsidian-connect-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.