List free STEP and STL downloads generated by Xem Studio from the standard for one hardware object (screws, nuts, washers, standoffs, inserts, dowels, magnets, pipe, tri-clamp parts, LM8UU). Returns direct URLs; CC BY 4.0; threads modeled as plain cylinders at major diameter.
| Name | Required | Description | Default |
|---|---|---|---|
| filter | No | Substring of the part name, e.g. 'm3x10', '2in', 'ferrule' | |
| object | Yes |
Changes observed during successful MCP inspections.
Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
No annotations are provided, so the description carries the burden, and it discloses useful traits: results are direct URLs, content is CC BY 4.0, and threads are modeled as plain cylinders at major diameter. It does not cover pagination, rate limits, or result size, but the key modeling and licensing caveats are present.
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 dense sentences with the core purpose front-loaded and no wasted text. The parenthetical examples and behavioral caveats are compact and directly relevant.
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?
For a simple list/download tool with no output schema, the description explains the return type as direct URLs and adds licensing and modeling caveats. It is mostly complete, though it could say more about result structure or pagination behavior.
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 only 50%, but the description compensates for the undocumented required object parameter by listing valid hardware object categories. The optional filter parameter is documented in the schema with examples, so both parameters have usable semantics even though the object list may not be exhaustive.
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 states a specific verb and resource: listing free STEP/STL downloads for one hardware object. It scopes the tool clearly with examples of object types, though it does not explicitly contrast itself with siblings like get_geometry or find_geometry.
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?
Usage is implied by the focus on free downloads for a single hardware object, and the parenthetical lists eligible object types. However, it gives no explicit when-to-use guidance versus siblings such as get_geometry or find_geometry, and does not explain when to use the optional filter.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.
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