list_roles
AI agents call list_roles to retrieve information from Awslabs Valkey without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
List operations retrieve and enumerate data without modifying state. The name strongly suggests enumeration of role objects. Even with an empty description, this follows standard AWS API naming conventions for read-only queries. Severity is low because listing roles discloses information about permissions structure but does not directly execute code, modify data, or cause external effects.
From the tool's definition Tool name 'list_roles' indicates a query/retrieval operation. Description is empty, but the verb 'list' is a canonical Read operation that retrieves information without side effects. Consistent with AWS IAM patterns where ListRoles is a read-only permission.
Attacks that exploit this kind of access
list_roles. It is categorised as a Read tool in the Awslabs Valkey MCP Server, which means it retrieves data without modifying state.
Register the Awslabs Valkey MCP server in PolicyLayer and add a rule for list_roles: 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 Awslabs Valkey. Nothing to install.
list_roles 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 list_roles 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 list_roles. 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.
list_roles is provided by the Awslabs Valkey MCP server (awslabs.valkey-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.