# echo

入力されたメッセージをそのまま返す簡単なツール

Agent View of the PolicyLayer registry record for `echo`. HTML page: https://policylayer.com/tools/109naoki-minimal-mcp-server/echo

## Facts

- Tool: `echo`
- Server: Minimal (`109naoki/minimal-mcp-server`) — https://policylayer.com/tools/109naoki-minimal-mcp-server.md
- Homepage: https://github.com/109naoki/minimal-mcp-server
- Risk category: Read (Low risk)
- Registry record: grade A, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Allowed

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

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

## Why echo is rated Low

This is a simple echo function that retrieves and returns the exact input provided. It performs no operations on data beyond retrieval, creates no new data, executes no commands, and has no side effects. It is purely informational and read-like in nature, making it the lowest-risk category.

From the tool's own definition: "Tool name: 'echo'. Description: '入力されたメッセージをそのまま返す簡単なツール' (translates to 'A simple tool that returns the input message as is'). The tool accepts input and returns it without modification or side effects."

## Use case

AI agents call echo to retrieve information from Minimal without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

## Recommended policy (PolicyLayer)

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

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "echo": {}
  }
}
```

## Other tools on Minimal (2)

- `get-current-time` — Read — https://policylayer.com/tools/109naoki-minimal-mcp-server/get-current-time.md
- `search-wikipedia` — Read — https://policylayer.com/tools/109naoki-minimal-mcp-server/search-wikipedia.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=109naoki-minimal-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/109naoki-minimal-mcp-server