vim_buffer_save · Mcp Neovim Server MCP: Risk & Policy

WHAT IT DOES

What vim_buffer_save does on Mcp Neovim Server

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

WHY IT NEEDS A POLICY

Why vim_buffer_save needs a policy

This tool writes/modifies files on the system. It is reversible (files can be edited or deleted afterward), so it is Write rather than Destructive. Severity is medium because an AI agent could overwrite important files, but this is less severe than irreversible deletion. The confidence is high because the intent is unambiguous from both name and description.

From the tool's definition Tool name 'vim_buffer_save' and description 'Save current buffer or save to specific filename' indicate file write operations. The action persists data to disk.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vim_buffer_save Rate-limited

vim_buffer_save 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": {
    "vim_buffer_save": {
      "limits": [
        {
          "counter": "vim_buffer_save_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 Neovim Server, so you can run agents against it safely.

FAQ

Questions about vim_buffer_save

What does the vim_buffer_save tool do? +

Save current buffer or save to specific filename. It is categorised as a Write tool in the Mcp Neovim Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on vim_buffer_save? +

Register the Mcp Neovim Server MCP server in PolicyLayer and add a rule for vim_buffer_save: 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 Neovim Server. Nothing to install.

What risk level is vim_buffer_save? +

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

Can I rate-limit vim_buffer_save? +

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

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

vim_buffer_save is provided by the Mcp Neovim Server MCP server (mcp-neovim-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.