# biome-format

Formats files with Biome (format --write) and returns a structured list of changed files.

Agent View of the PolicyLayer registry record for `biome-format`. HTML page: https://policylayer.com/tools/io-github-dave-london-github/biome-format

## Facts

- Tool: `biome-format`
- Server: Github (`@paretools/github`) — https://policylayer.com/tools/io-github-dave-london-github.md
- Install: `npx -y @paretools/github`
- Homepage: https://github.com/Dave-London/Pare
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "biome-format",
    "arguments": {}
  }
}
```

## Why biome-format is rated Medium

This tool modifies files on the filesystem by applying code formatting via Biome. While formatting changes are typically reversible (the original code is still in version control or backups), the tool directly overwrites file contents. This is a Write operation rather than Destructive because formatting is generally reversible and doesn't permanently destroy data.

From the tool's own definition: "Tool description states 'Formats files with Biome (format --write)' which modifies files in place using the --write flag, and 'returns a structured list of changed files' confirming write operations occur."

## Use case

AI agents use biome-format to create or update resources in Github, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Github environment.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches Github:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "biome-format": {
      "limits": [
        {
          "counter": "biome-format_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Github (201)

- `branch` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/branch.md
- `clean` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/clean.md
- `remove` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/remove.md
- `reset` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/reset.md
- `secret-delete` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/secret-delete.md
- `stash` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/stash.md
- `tag` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/tag.md
- `variable-delete` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/variable-delete.md
- `workspace` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/workspace.md
- `worktree` — Destructive — https://policylayer.com/tools/io-github-dave-london-github/worktree.md
- `add` — Execute — https://policylayer.com/tools/io-github-dave-london-github/add.md
- `add-package` — Execute — https://policylayer.com/tools/io-github-dave-london-github/add-package.md
- `ansible-galaxy` — Execute — https://policylayer.com/tools/io-github-dave-london-github/ansible-galaxy.md
- `ansible-playbook` — Execute — https://policylayer.com/tools/io-github-dave-london-github/ansible-playbook.md
- `api` — Execute — https://policylayer.com/tools/io-github-dave-london-github/api.md
- `apply` — Execute — https://policylayer.com/tools/io-github-dave-london-github/apply.md
- `audit` — Execute — https://policylayer.com/tools/io-github-dave-london-github/audit.md
- `bazel` — Execute — https://policylayer.com/tools/io-github-dave-london-github/bazel.md
- `biome-check` — Execute — https://policylayer.com/tools/io-github-dave-london-github/biome-check.md
- `bisect` — Execute — https://policylayer.com/tools/io-github-dave-london-github/bisect.md
- `black` — Execute — https://policylayer.com/tools/io-github-dave-london-github/black.md
- `build` — Execute — https://policylayer.com/tools/io-github-dave-london-github/build.md
- `bundle-exec` — Execute — https://policylayer.com/tools/io-github-dave-london-github/bundle-exec.md
- `bundle-install` — Execute — https://policylayer.com/tools/io-github-dave-london-github/bundle-install.md
- `check` — Execute — https://policylayer.com/tools/io-github-dave-london-github/check.md
- `cherry-pick` — Execute — https://policylayer.com/tools/io-github-dave-london-github/cherry-pick.md
- `clippy` — Execute — https://policylayer.com/tools/io-github-dave-london-github/clippy.md
- `cmake` — Execute — https://policylayer.com/tools/io-github-dave-london-github/cmake.md
- `compose-build` — Execute — https://policylayer.com/tools/io-github-dave-london-github/compose-build.md
- `compose-down` — Execute — https://policylayer.com/tools/io-github-dave-london-github/compose-down.md
- …and 171 more: https://policylayer.com/tools/io-github-dave-london-github.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=io-github-dave-london-github · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/io-github-dave-london-github