Fusion360 MCP Server

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

Annotations already indicate this is a non-readonly, non-idempotent, non-destructive operation. The description adds minimal context beyond this - it specifies 'new component (sub-assembly)' which clarifies the type of object being created, but doesn't address behavioral aspects like permissions needed, what happens on duplicate names, or response format.

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, efficient sentence that gets straight to the point with zero wasted words. It's appropriately sized for a simple creation tool and front-loads the essential 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 creation tool with good annotations (readOnlyHint=false, destructiveHint=false) and full schema coverage, the description is minimally adequate. However, without an output schema and with many similar sibling tools, it could benefit from more context about what constitutes a 'component' versus other creatable objects and what the tool returns.

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?

With 100% schema description coverage, the schema already documents both parameters thoroughly. The description doesn't add any parameter-specific information beyond what's in the schema - no examples, formatting details, or clarification about the parent-child relationship implied by 'sub-assembly'.

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 the action ('Create') and resource ('new component (sub-assembly) in the design'), making the purpose immediately understandable. However, it doesn't explicitly differentiate from sibling tools like 'create_box' or 'create_cylinder' that also create objects but of different types.

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. With many sibling 'create_' tools (e.g., create_box, create_cylinder, create_sketch), there's no indication of when a component is appropriate versus other object types, nor any prerequisites or exclusions mentioned.

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