# create_datum_line

A write tool on the FreeCAD Robust MCP Server MCP server.

Agent View of the PolicyLayer registry record for `create_datum_line`. HTML page: https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/create-datum-line

## Facts

- Tool: `create_datum_line`
- Server: FreeCAD Robust MCP Server (`spkane/freecad-addon-robust-mcp-server`) — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server.md
- Homepage: https://github.com/spkane/freecad-addon-robust-mcp-server
- Risk category: Write (Medium risk)
- Registry record: grade F, identity unverified
- Server rate-limited: no
- Parameters: 0
- Recommended policy verdict: Rate-limited

## Example call (MCP tools/call, JSON-RPC 2.0)

```json
{
  "jsonrpc": "2.0",
  "id": 1,
  "method": "tools/call",
  "params": {
    "name": "create_datum_line",
    "arguments": {}
  }
}
```

## Why create_datum_line is rated Medium

This tool creates a datum line object in FreeCAD, which is a reversible Write operation (objects can be deleted). While it modifies the CAD model state, datum lines are standard modeling elements that can be undone or removed. The impact is limited to the CAD project file being edited, not the underlying system.

From the tool's own definition: "Tool name 'create_datum_line' indicates creation of a geometric datum object in FreeCAD. The sibling tools (add_sketch_arc, add_sketch_circle, add_sketch_line, etc.) are all geometry creation operations."

## Use case

AI agents use create_datum_line 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.

## Recommended policy (PolicyLayer)

Verdict: **Rate-limited**. Enforced by the PolicyLayer MCP gateway (https://policylayer.com/mcp-gateway) before a call reaches FreeCAD Robust MCP Server:

```json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "create_datum_line": {
      "limits": [
        {
          "counter": "create_datum_line_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}
```

## Other tools on FreeCAD Robust MCP Server (151)

- `close_document` — Destructive — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/close-document.md
- `delete_macro` — Destructive — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/delete-macro.md
- `delete_object` — Destructive — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/delete-object.md
- `delete_sketch_constraint` — Destructive — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/delete-sketch-constraint.md
- `delete_sketch_geometry` — Destructive — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/delete-sketch-geometry.md
- `spreadsheet_clear_cell` — Destructive — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/spreadsheet-clear-cell.md
- `activate_workbench` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/activate-workbench.md
- `boolean_operation` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/boolean-operation.md
- `draft_extrude_shapestring` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/draft-extrude-shapestring.md
- `execute_python` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/execute-python.md
- `explode_compound` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/explode-compound.md
- `part_sweep` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/part-sweep.md
- `recompute` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/recompute.md
- `recompute_document` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/recompute-document.md
- `revolution_sketch` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/revolution-sketch.md
- `run_macro` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/run-macro.md
- `safe_execute` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/safe-execute.md
- `scale_object` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/scale-object.md
- `set_camera_position` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/set-camera-position.md
- `shell_object` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/shell-object.md
- `slice_shape` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/slice-shape.md
- `subtractive_loft` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/subtractive-loft.md
- `subtractive_pipe` — Execute — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/subtractive-pipe.md
- `common_all` — Other — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/common-all.md
- `draft_feature` — Other — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/draft-feature.md
- `draft_shapestring_to_face` — Other — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/draft-shapestring-to-face.md
- `draft_text_on_surface` — Other — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/draft-text-on-surface.md
- `section_shape` — Other — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/section-shape.md
- `set_display_mode` — Other — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/set-display-mode.md
- `set_view_angle` — Other — https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server/set-view-angle.md
- …and 121 more: https://policylayer.com/tools/spkane-freecad-addon-robust-mcp-server.md

## For agents

This record is a snapshot. Live verdicts and the full registry:

- Check every server in your MCP config at once: `npx -y policylayer stack`
- Vet a server before you add it: install the mcp-precheck skill — `npx skills add https://policylayer.com` (skill text: https://policylayer.com/skill.md)
- Query the registry over MCP: endpoint `https://api.policylayer.com/mcp` — tools `check_mcp_server`, `check_mcp_stack`, `check_tool`, `search_registry`, `get_change_events`

---

Source: the PolicyLayer MCP registry — one continuously verified record per MCP server. Full record: https://policylayer.com/registry?q=spkane-freecad-addon-robust-mcp-server · API: https://policylayer.com/registry/api · Policy library: https://policylayer.com/policies/spkane-freecad-addon-robust-mcp-server
