scaffold_extension
Give a COMP a Python extension class: create a Text DAT holding the class (with optional method stubs), wire it into an extension slot, optionally promote it (so members are callable directly on the COMP), and reinitialize. The other half of making a generated network reusable — pair with
This record as markdown: /tools/io-github-pantani-tdmcp/scaffold-extension.md
What scaffold_extension does on tdmcp — TouchDesigner MCP server
AI agents use scaffold_extension to create or update resources in tdmcp — TouchDesigner MCP server, usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your tdmcp — TouchDesigner MCP server environment.
Why scaffold_extension is rated Medium
The tool creates and wires new components (Text DAT, extension class) into a TouchDesigner network and reinitializes the COMP. This is a reversible write/create operation — it adds and configures data but does not irreversibly destroy existing content. The reinitialization could have side effects on a live system, but the primary action is creating and modifying network nodes.
From the tool's definition create a Text DAT holding the class (with optional method stubs), wire it into an extension slot, optionally promote it, and reinitialize
Attacks that exploit this kind of access
The rule that runs scaffold_extension safely
PolicyLayer is an MCP gateway: it sits between your AI agents and tdmcp — TouchDesigner MCP server, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For scaffold_extension, this is the rule to start with:
scaffold_extension stays usable, but capped: an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
The button opens the PolicyLayer dashboard: create your workspace, connect tdmcp — TouchDesigner MCP server, apply this rule, and every scaffold_extension call is checked against it from then on.
Questions about scaffold_extension
Give a COMP a Python extension class: create a Text DAT holding the class (with optional method stubs), wire it into an extension slot, optionally promote it (so members are callable directly on the COMP), and reinitialize. The other half of making a generated network reusable — pair with. It is categorised as a Write tool in the tdmcp — TouchDesigner MCP server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the tdmcp — TouchDesigner MCP server MCP server in PolicyLayer and add a rule for scaffold_extension: 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 tdmcp — TouchDesigner MCP server. Nothing to install.
scaffold_extension is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the scaffold_extension 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 scaffold_extension. 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.
scaffold_extension is provided by the tdmcp — TouchDesigner MCP server MCP server (@dpantani/tdmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
More on tdmcp — TouchDesigner MCP server, and thousands of servers like it.
This server
Across the catalogue