サーバーを最新バージョンにアップデートする。git pull + 依存関係の更新を行います。
AI agents invoke update_server to trigger actions in JVLink MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.
This tool executes shell-level operations (git pull and dependency installation) on the server environment. It is not purely destructive but it does execute external commands that modify the server's running state and installed packages. The blast radius is high because a misuse (e.g., pulling malicious code or breaking dependencies) could destabilize the server.
From the tool's definition 「git pull + 依存関係の更新を行います」— runs git pull and dependency updates on the server, triggering external operations with system-level effects
Documented attack patterns abuse exactly the kind of access update_server gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and JVLink MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for update_server:
{
"version": "1",
"default": "deny",
"tools": {
"update_server": {
"limits": [
{
"counter": "update_server_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}update_server stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
サーバーを最新バージョンにアップデートする。git pull + 依存関係の更新を行います。. It is categorised as a Execute tool in the JVLink MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the JVLink MCP Server MCP server in PolicyLayer and add a rule for update_server: 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 JVLink MCP Server. Nothing to install.
update_server is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.
Yes. Add a rate_limit block to the update_server 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 update_server. 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.
update_server is provided by the JVLink MCP Server MCP server (miyamamoto/jvlink-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from JVLink 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.
25 JVLink MCP Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.