ruff-format

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

SERVERBuild 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-build/ruff-format.md

WHAT IT DOES

What ruff-format does on Build

AI agents invoke ruff-format to trigger actions in Build. 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 an external command (ruff format) that modifies source files by reformatting them. While formatting is generally reversible via version control, it does modify files on disk. The most severe applicable category is Execute since it triggers an external operation whose effects depend on arguments (which files to format).

From the tool's definition 'Runs ruff format' — actively executes the ruff formatter tool against files

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 Build, 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 Build, 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 Build 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 Build 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 Build. 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 Build 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 Build, and thousands of servers like it.

This server

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Guides

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