This record as markdown: /tools/hybridlabor-api-aos/exec-node-method.md
What exec_node_method does on Aos
AI agents invoke exec_node_method to trigger actions in Aos. 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 exec_node_method is rated High
This tool allows invocation of arbitrary Python methods on TouchDesigner nodes without constraints. The 'escape hatch' language confirms it bypasses normal safeguards. Arbitrary code execution is the highest-risk Execute operation because an AI agent could invoke malicious methods, access system resources, or trigger unintended side effects in the TouchDesigner environment.
From the tool's definition Tool name 'exec_node_method' combined with description 'invoke an arbitrary Python method on a node' and 'Escape hatch' indicates execution of arbitrary Python code.
Attacks that exploit this kind of access
The rule that runs exec_node_method safely
PolicyLayer is an MCP gateway: it sits between your AI agents and Aos, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For exec_node_method, this is the rule to start with:
exec_node_method 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 Aos, apply this rule, and every exec_node_method call is checked against it from then on.
Questions about exec_node_method
Escape hatch — invoke an arbitrary Python method on a node (operator). Prefer structured tools where one exists; use this for operations they don. It is categorised as a Execute tool in the Aos MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.
Register the Aos MCP server in PolicyLayer and add a rule for exec_node_method: 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 Aos. Nothing to install.
exec_node_method 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 exec_node_method 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 exec_node_method. 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.
exec_node_method is provided by the Aos MCP server (@hybridlabor-api/aos). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
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