AI agents call echo to retrieve information from Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool merely returns input to output without accessing, modifying, or executing anything. It has no blast radius for misuse—the worst outcome is redundant echoed text. Categorized as Read (information reflection with no side effects) rather than Other since it does technically process and return data, albeit trivially.
From the tool's definition Tool name 'echo' and description 'Echo back a message' indicate a simple reflection/feedback operation with no data retrieval, modification, execution, or side effects.
Attacks that exploit this kind of access
Echo back a message. It is categorised as a Read tool in the Server MCP Server, which means it retrieves data without modifying state.
Register the Server MCP server in PolicyLayer and add a rule for echo: 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 Server. Nothing to install.
echo is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the echo 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.
Set action: deny in the PolicyLayer policy for echo. 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.
echo is provided by the Server MCP server (@nest-mcp/server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →