AI agents call list_activities to retrieve information from Jikan without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
This tool queries and returns a list of activity types without creating, modifying, deleting, or executing any operations. It is a pure read operation with minimal security risk, as it only exposes metadata about available activities to the user.
From the tool's definition Tool name 'list_activities' and description 'List available activity types' indicate a retrieval operation with no modifications.
Attacks that exploit this kind of access
List available activity types (FREE, PUBLIC, and your PRIVATE). Free (0 credits). It is categorised as a Read tool in the Jikan MCP Server, which means it retrieves data without modifying state.
Register the Jikan MCP server in PolicyLayer and add a rule for list_activities: 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 Jikan. Nothing to install.
list_activities 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_activities 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_activities. 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_activities is provided by the Jikan MCP server (thunderrabbit/jikan). 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 →