gem-list
Lists installed Ruby gems with version information. Returns structured JSON with gem names and versions.
This record as markdown: /tools/io-github-dave-london-http/gem-list.md
What gem-list does on Http
AI agents call gem-list to retrieve information from Http without modifying anything. It is typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
Why gem-list is rated Low
The tool performs a read-only operation that retrieves and lists local system information (installed gems). It does not modify, delete, execute code, or make financial transactions. The action is passive data retrieval, fitting the Read category with low severity due to minimal risk of harm even if misused.
From the tool's definition Tool description states it 'Lists installed Ruby gems with version information' and 'Returns structured JSON with gem names and versions.' This is a pure query/enumeration operation with no modification or side effects.
Attacks that exploit this kind of access
The rule that runs gem-list safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Http, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For gem-list, this is the rule to start with:
gem-list is read-only, so it stays allowed. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect Http, apply this rule, and every gem-list call is checked against it from then on.
Questions about gem-list
Lists installed Ruby gems with version information. Returns structured JSON with gem names and versions. It is categorised as a Read tool in the Http MCP Server, which means it retrieves data without modifying state.
Register the Http MCP server in PolicyLayer and add a rule for gem-list: 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 Http. Nothing to install.
gem-list 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 gem-list 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 gem-list. 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.
gem-list is provided by the Http MCP server (@paretools/http). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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