monty_run
Run deterministic, sandboxed Python-subset code (Monty) for fast local computation and post-processing.
This record as markdown: /tools/cowork-os/monty-run.md
What monty_run does on CoWork OS
AI agents invoke monty_run to trigger actions in CoWork OS. 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.
Why monty_run is rated High
Code execution tools are classified as Execute because they trigger external operations (code evaluation) whose side effects depend on the arguments provided. Although this tool has mitigations (sandboxing, Python subset), it still permits running code that could inadvertently access file systems, make network calls if permitted by the sandbox, or perform unwanted computations.
From the tool's definition 'Run deterministic, sandboxed Python-subset code' indicates the tool executes code. While sandboxing and the 'Python-subset' constraint limit scope, the capability to execute arbitrary code is fundamentally an Execute operation.
Attacks that exploit this kind of access
The rule that runs monty_run safely
PolicyLayer is an MCP gateway: it sits between your AI agents and CoWork OS, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For monty_run, this is the rule to start with:
monty_run 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.
The button opens the PolicyLayer dashboard: create your workspace, connect CoWork OS, apply this rule, and every monty_run call is checked against it from then on.
Questions about monty_run
Run deterministic, sandboxed Python-subset code (Monty) for fast local computation and post-processing. It is categorised as a Execute tool in the CoWork OS MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the CoWork OS MCP server in PolicyLayer and add a rule for monty_run: 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 CoWork OS. Nothing to install.
monty_run 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 monty_run 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 monty_run. 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.
monty_run is provided by the CoWork OS MCP server (CoWork-OS/CoWork-OS). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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