Creates a list by running a shell command and parsing its newline-delimited output. WHEN TO USE: - When you need to create a list from command output (e.g., find, ls, grep, git ls-files) - When the list of items to process is determined by a shell command - As an alternative to manually specifyin...
AI agents invoke create_list_from_shell to trigger actions in Par5. 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 commands on the host system to generate list content. While the primary purpose is list creation (Write), the mechanism involves running arbitrary shell commands, which can have wide-ranging side effects depending on the command provided.
From the tool's definition 'Creates a list by running a shell command and parsing its newline-delimited output' — explicitly runs arbitrary shell commands (e.g., find, ls, grep, git ls-files)
Documented attack patterns abuse exactly the kind of access create_list_from_shell gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Par5, and nothing reaches the server without passing your rules. This is the rule we recommend for create_list_from_shell:
{
"version": "1",
"default": "deny",
"tools": {
"create_list_from_shell": {
"limits": [
{
"counter": "create_list_from_shell_rate",
"window": "minute",
"max": 10,
"scope": "grant"
}
]
}
}
}create_list_from_shell 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.
Creates a list by running a shell command and parsing its newline-delimited output. WHEN TO USE: - When you need to create a list from command output (e.g., find, ls, grep, git ls-files) - When the list of items to process is determined by a shell command - As an alternative to manually specifying items in create_list EXAMPLES: -. It is categorised as a Execute tool in the Par5 MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Par5 MCP server in PolicyLayer and add a rule for create_list_from_shell: 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 Par5. Nothing to install.
create_list_from_shell 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 create_list_from_shell 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 create_list_from_shell. 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.
create_list_from_shell is provided by the Par5 MCP server (mathematic-inc/par5-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Par5, 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.
8 Par5 tools catalogued and risk-classified — across an index of 43,000+ MCP servers.