Fusion360 MCP Server

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

Annotations indicate this is a mutable, non-idempotent, non-destructive operation (readOnlyHint: false, idempotentHint: false, destructiveHint: false), which the description does not contradict. The description adds minimal behavioral context beyond annotations, as it only mentions the sweep action without detailing effects like geometry creation or potential errors. However, it does not provide additional insights into rate limits, authentication needs, or specific outcomes.

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 directly states the tool's action without unnecessary words. It is front-loaded with the core functionality, making it easy to parse quickly. There is no wasted verbiage, adhering well to the principle of conciseness.

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 the complexity of a 3D modeling operation with 4 parameters, low schema coverage, no output schema, and annotations that only cover basic hints, the description is insufficient. It lacks details on parameter meanings, expected outcomes, error conditions, or how it integrates with sibling tools. This leaves significant gaps for an agent to understand and invoke the tool effectively in context.

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 low at 25%, with only one parameter ('path_sketch_name') having a description. The tool description does not compensate by explaining parameters like 'profile_index', 'path_curve_index', or the 'operation' enum values (e.g., 'new_body', 'join'). This leaves key inputs poorly documented, hindering the agent's ability to use them correctly without external knowledge.

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 ('sweep') and the resources involved ('a sketch profile along a path (sketch curve)'), making the purpose understandable. However, it does not explicitly differentiate this tool from sibling tools like 'extrude', 'revolve', or 'loft', which also create 3D geometry from sketches, leaving some ambiguity about when to choose sweep over those alternatives.

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 'extrude' for linear paths or 'revolve' for circular ones. It also lacks information about prerequisites, like needing existing sketches, or exclusions, such as invalid path types. Without such context, the agent must infer usage from the tool name and parameters alone.

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