AI agents call skill_list_all to retrieve information from ClaudeSkills MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
The 'list_all' naming pattern combined with the server's stated purpose of discovery and reading (without modification or execution) strongly suggests this tool retrieves or enumerates data without side effects. Although the description is empty, the naming convention and sibling tools provide sufficient context. No evidence of data modification, deletion, code execution, or financial operations is present.
From the tool's definition Tool name 'skill_list_all' and sibling tools with patterns like 'skill_list_assets', 'skill_list_notes', 'skill_search_index', and 'skill_read_asset' indicate retrieval/query operations.
Risk signalsBulk/mass operation — affects multiple targets
Documented attack patterns abuse exactly the kind of access skill_list_all gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and ClaudeSkills MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for skill_list_all:
{
"version": "1",
"default": "deny",
"tools": {
"skill_list_all": {}
}
}skill_list_all is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.
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skill_list_all. It is categorised as a Read tool in the ClaudeSkills MCP Server MCP Server, which means it retrieves data without modifying state.
Register the ClaudeSkills MCP Server MCP server in PolicyLayer and add a rule for skill_list_all: 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 ClaudeSkills MCP Server. Nothing to install.
skill_list_all 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 skill_list_all 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 skill_list_all. 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.
skill_list_all is provided by the ClaudeSkills MCP Server MCP server (tsoernes/skills-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from ClaudeSkills MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
13 ClaudeSkills MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.