Pick CAD entities by handle to highlight them in the viewer for focused inspection or editing.
Select entities by handle and highlight them.
| Name | Required | Description | Default |
|---|---|---|---|
| handles | Yes | Entity handles to select (replaces the selection) |
Changes observed during successful MCP inspections.
v1.0.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
Annotations already declare readOnlyHint=true and openWorldHint=false, so safety is covered; the description usefully adds that entities are highlighted as a visible side effect. However, it omits the key behavioral fact stated only in the schema — that the call replaces the existing selection — and says nothing about what happens with invalid or unknown handles.
Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.
Is the description appropriately sized, front-loaded, and free of redundancy?
One front-loaded sentence with no filler and the effect stated immediately. It is arguably too terse given the missing selection-replacement semantics, but nothing is wasted.
Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.
Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?
A one-parameter tool with annotations and a fully covered schema needs little, but the description leaves out the selection-replacement behavior and any indication of what the call returns (e.g., new selection set or confirmation). Sibling interaction (select_window, clear) is also unaddressed.
Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.
Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?
Schema coverage is 100% and the single parameter is fully documented in the schema, so baseline 3 applies. The description confirms the handle-based addressing but adds no format detail (handle syntax, batching) beyond the schema.
Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.
Does the description clearly state what the tool does and how it differs from similar tools?
States a specific verb and resource ("Select entities by handle") plus the visible effect (highlighting), so the action is unambiguous. It does not distinguish itself from siblings like select_window or clear, which an agent must infer from names alone.
Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.
Does the description explain when to use this tool, when not to, or what alternatives exist?
There is no guidance on when to use this versus select_window (window/region selection) or click, and no mention of how it relates to clear. The agent must guess the selection workflow from sibling names.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.