Identify overlapping parts in an Onshape assembly using bounding box detection, returning the interfering parts and overlap amounts.
Check for overlapping/interfering parts in an assembly using bounding box detection. Returns which parts overlap and by how much.
| Name | Required | Description | Default |
|---|---|---|---|
| elementId | Yes | Assembly element ID | |
| documentId | Yes | Document ID | |
| workspaceId | Yes | Workspace ID |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It does reveal that the tool uses bounding box detection (a behavioral detail implying approximation) and states the return type (overlap and amount). However, it omits caveats such as the approximate nature of bounding boxes potentially leading to false positives/negatives, or any side effects (which are likely none, being a read-only check). The disclosure is adequate but not rich.
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?
The description is two sentences with zero wasted words. It front-loads the core purpose and immediately states the output. The structure is clean and efficient, making it easy to parse for an agent.
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?
Given there is no output schema, the description must explain the return value. It does state the high-level result ('which parts overlap and by how much'), but it lacks detail such as the exact format (e.g., list of part IDs, units of overlap, behavior when no overlap exists). The tool is relatively simple, so this is a moderate gap, not a critical omission. The description is sufficient to understand the tool's function but not fully complete for precise invocation without additional inference.
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 description coverage is 100%, with each parameter having a basic description ('Assembly element ID', 'Document ID', 'Workspace ID'). The tool description adds no additional meaning about how these parameters are used or their relationships, so it stays at the baseline of 3. No extra value is provided 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?
The description clearly states a specific verb ('Check'), a resource ('assembly'), a method ('bounding box detection'), and the output ('which parts overlap and by how much'). This distinguishes it from siblings like get_bounding_box or measure, which have different purposes. The purpose is unambiguous and actionable.
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?
The description provides no guidance on when to use this tool versus alternatives. It does not mention any prerequisites, such as needing to load the assembly first, nor does it suggest when this tool is preferable to measure or get_bounding_box. There is no exclusionary language or alternative routing.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.