vault_patch · Connect MCP: Risk & Policy

WHAT IT DOES

What vault_patch does on Connect MCP

AI agents use vault_patch 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_patch needs a policy

This tool modifies note content reversibly by editing specific sections or creating missing heading targets. It does not delete data irreversibly (ruling out Destructive), does not execute arbitrary code (ruling out Execute), and does not create financial obligations.

From the tool's definition Tool description states 'Edit a specific section of a note' and 'targets are created if missing', indicating modification of note content. The tool name 'vault_patch' and verb 'Edit' confirm write operations.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vault_patch Rate-limited

vault_patch 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_patch": {
      "limits": [
        {
          "counter": "vault_patch_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_patch

What does the vault_patch tool do? +

Edit a specific section of a note. For headings: targets are created if missing. Tip: use vault_read first to understand the note structure before patching. 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_patch? +

Register the Connect MCP server in PolicyLayer and add a rule for vault_patch: 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_patch? +

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

Can I rate-limit vault_patch? +

Yes. Add a rate_limit block to the vault_patch 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_patch completely? +

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

vault_patch 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.