Get all field names from hash.
AI agents call hash_keys to retrieve information from Amazon ElastiCache Memcached MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool retrieves metadata (field names) from a hash object in Memcached. It performs a read-only query with no side effects—it neither modifies, executes, deletes, nor moves data. The blast radius is minimal: worst case, an agent learns the schema of cached data but cannot alter system state.
From the tool's definition Tool name 'hash_keys' combined with description 'Get all field names from hash' indicates a retrieval operation that queries the structure of a hash data structure without modifying or deleting data.
Attacks that exploit this kind of access
Get all field names from hash. It is categorised as a Read tool in the Amazon ElastiCache Memcached MCP Server MCP Server, which means it retrieves data without modifying state.
Register the Amazon ElastiCache Memcached MCP Server MCP server in PolicyLayer and add a rule for hash_keys: 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 ElastiCache Memcached MCP Server. Nothing to install.
hash_keys 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 hash_keys 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 hash_keys. 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.
hash_keys is provided by the Amazon ElastiCache Memcached MCP Server MCP server (awslabs.memcached-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.