List assembly features

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

The readOnlyHint annotation already tells the agent this is a safe read operation, lowering the burden on the description. The description adds a small behavioral detail by specifying exactly which kinds of features are listed (mates, connectors, groups) and that feature ids are included, but it does not disclose pagination, response format, or other runtime behaviors.

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 a single sentence with no filler or repetition. It front-loads the meaningful content — what the tool returns — and every word adds information.

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 read-only listing tool with three fully documented parameters, the description is mostly complete: it states the target resource (assembly) and the output contents (mates, connectors, groups with feature ids). The lack of an output schema makes the description the only source of return-value information, and it covers that adequately, though it could mention whether the result is a list or object.

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%, and every parameter already has a clear explanation tying doc, ws, and elem to URL segments. The description adds no additional parameter semantics, so the baseline score of 3 is appropriate.

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 names the specific content returned — mates, mate connectors, and groups defined in an assembly — and mentions feature ids, so an agent can tell this is an assembly-feature lister. It does not use an explicit verb like 'List', but the title and tool name supply that, and the resource scope is clear enough to distinguish it from generic feature tools.

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 such as onshape_get_features or onshape_get_assembly. It implies assembly feature listing but does not state exclusions, prerequisites, or selection criteria, leaving the agent to infer the right context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.