ruff-format

Runs ruff format and returns structured results (files changed, file list).

SERVERNpm SOURCEDave-London/Pare

High RISK CLASS

Category Execute

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-dave-london-npm/ruff-format.md

WHAT IT DOES

What ruff-format does on Npm

AI agents invoke ruff-format to trigger actions in Npm. 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.

RISK

Why ruff-format is rated High

This tool executes the ruff formatter tool against files, which actively modifies source code files. It runs an external command and changes file contents. While formatting is generally reversible via version control, it does modify files in place, making it Execute (with Write characteristics). The blast radius is medium as it could reformat code files in unexpected ways if pointed at the wrong directory.

From the tool's definition Runs ruff format and returns structured results (files changed, file list)

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs ruff-format safely

PolicyLayer is an MCP gateway: it sits between your AI agents and Npm, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For ruff-format, this is the rule to start with:

ruff-format Rate-limited

ruff-format 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": {
    "ruff-format": {
      "limits": [
        {
          "counter": "ruff-format_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect Npm, apply this rule, and every ruff-format call is checked against it from then on.

FAQ

Questions about ruff-format

What does the ruff-format tool do? +

Runs ruff format and returns structured results (files changed, file list). It is categorised as a Execute tool in the Npm MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on ruff-format? +

Register the Npm MCP server in PolicyLayer and add a rule for ruff-format: 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 Npm. Nothing to install.

What risk level is ruff-format? +

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

Can I rate-limit ruff-format? +

Yes. Add a rate_limit block to the ruff-format 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 ruff-format completely? +

Set action: deny in the PolicyLayer policy for ruff-format. 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 ruff-format? +

ruff-format is provided by the Npm MCP server (Dave-London/Pare). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

More on Npm, and thousands of servers like it.

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Guides

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