Fusion360 MCP Server

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

Annotations already indicate this is a mutable operation (readOnlyHint: false) that's non-destructive and non-idempotent. The description adds minimal behavioral context beyond this - it specifies the sketch context ('most recent sketch') but doesn't describe what happens if no sketch exists, whether the rectangle becomes a sketch entity, or any other behavioral details. The description doesn't contradict annotations.

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 states the core functionality without unnecessary words. It's appropriately sized for a straightforward drawing operation 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 5-parameter drawing tool with no output schema and minimal annotations, the description is incomplete. It doesn't explain what the tool returns, how errors are handled, or provide usage examples. While the purpose is clear, the lack of parameter guidance and behavioral context leaves significant gaps for an AI agent trying to use this tool effectively.

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 0% schema description coverage, the description carries full burden for parameter explanation but provides none. However, the parameter names (width, height, origin_x/y/z) are self-explanatory for rectangle drawing in a 3D context. The description implies these parameters define the rectangle's dimensions and position, though it doesn't explicitly explain their meaning or units.

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 ('Draw') and the resource ('a rectangle'), specifying it operates 'in the most recent sketch'. This distinguishes it from sibling tools like 'create_box' or 'create_polygon' by focusing on sketch-based rectangle drawing rather than 3D primitive creation.

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 like 'create_box' or 'create_polygon'. It mentions 'most recent sketch' which implies a prerequisite sketch context, but doesn't explicitly state when this tool is appropriate or what alternatives exist for different scenarios.

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