Add a slot (obround/stadium shape) to a sketch. A slot is two semicircles connected by parallel lines. Args: sketch_name: Name of the sketch to add slot to. center1_x: X coordinate of first arc center. center1_y: Y coordinate of first arc center. center2_x: X coordinate of second arc center. cent...
AI agents use add_sketch_slot to create or update resources in FreeCAD Robust MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your FreeCAD Robust MCP Server environment.
This tool creates new geometric elements within a FreeCAD sketch by adding a slot shape. This is a write operation as it modifies sketch data reversibly—the addition can be undone in FreeCAD's standard undo/redo workflow. It does not execute arbitrary code, delete data, or affect external systems, so it does not rise to Execute or Destructive severity.
From the tool's definition Tool description states 'Add a slot (obround/stadium shape) to a sketch' with parameters for creating geometric shapes. The verb 'Add' and the function of creating new sketch geometry indicates a write operation that modifies the sketch reversibly.
Documented attack patterns abuse exactly the kind of access add_sketch_slot gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and FreeCAD Robust MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for add_sketch_slot:
{
"version": "1",
"default": "deny",
"tools": {
"add_sketch_slot": {
"limits": [
{
"counter": "add_sketch_slot_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}add_sketch_slot 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.
Free to start. No card required.
Add a slot (obround/stadium shape) to a sketch. A slot is two semicircles connected by parallel lines. Args: sketch_name: Name of the sketch to add slot to. center1_x: X coordinate of first arc center. center1_y: Y coordinate of first arc center. center2_x: X coordinate of second arc center. center2_y: Y coordinate of second arc center. radius: Radius of the semicircular ends. doc_name: Document containing the sketch. Uses active document if None. Returns: Dictionary with geometry info: - first_geometry_index: Index of first geometry element - geometry_count: Total geometry elements. It is categorised as a Write tool in the FreeCAD Robust MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the FreeCAD Robust MCP Server MCP server in PolicyLayer and add a rule for add_sketch_slot: 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 FreeCAD Robust MCP Server. Nothing to install.
add_sketch_slot 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 add_sketch_slot 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 add_sketch_slot. 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.
add_sketch_slot is provided by the FreeCAD Robust MCP Server MCP server (spkane/freecad-addon-robust-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Deterministic rules across all 152 FreeCAD Robust MCP Server tools. Per-identity grants. Full audit log. Live in minutes. Nothing to install.
Free to start. No card required.
152 FreeCAD Robust MCP Server tools catalogued and risk-classified — across an index of 42,500+ MCP servers.