Get substring.
AI agents call string_get_range to retrieve information from Amazon MQ MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This is a basic string utility function that queries/extracts data (a substring) from an input string. It performs no modifications, deletions, execution, or financial operations. The operation is purely informational and has no blast radius if misused by an AI agent.
From the tool's definition Tool name 'string_get_range' and description 'Get substring' indicate a read-only operation that retrieves a portion of a string without modification or side effects.
Attacks that exploit this kind of access
Get substring. It is categorised as a Read tool in the Amazon MQ MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Amazon MQ MCP Server MCP server in PolicyLayer and add a rule for string_get_range: 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 Amazon MQ MCP Server. Nothing to install.
string_get_range 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 string_get_range 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 string_get_range. 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.
string_get_range is provided by the Amazon MQ MCP Server MCP server (awslabs.amazon-mq-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.