# yq

Processes and transforms YAML, JSON, XML, TOML, and properties files using yq expressions. Accepts input from a file path or inline string. Returns the transformed result.

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

## Facts

- Tool: `yq`
- Server: Npm (`Dave-London/Pare`) — https://policylayer.com/tools/io-github-dave-london-npm.md
- Homepage: https://github.com/Dave-London/pare
- Risk category: Execute (High 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": "yq",
    "arguments": {}
  }
}
```

## Why yq is rated High

The tool executes arbitrary yq expressions against files or inline data. yq expressions can read, modify, and write back structured data files. Since it accepts arbitrary expressions and can write transformed results (potentially back to files), this goes beyond a simple read operation.

From the tool's own definition: "Processes and transforms YAML, JSON, XML, TOML, and properties files using yq expressions"

## Use case

AI agents invoke yq 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.

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "yq": {
      "limits": [
        {
          "counter": "yq_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on Npm (201)

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