Fusion360 MCP Server

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

Annotations indicate this is a non-read-only, non-idempotent, non-destructive operation, which the description doesn't contradict. The description adds context about operating on 'the most recent sketch', which is useful behavioral information not covered by annotations. However, it lacks details on error conditions, visual feedback, or interaction with other sketch elements.

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, clear sentence that efficiently communicates the core functionality without unnecessary words. It's appropriately sized for a simple 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 geometry creation tool with 4 parameters, 0% schema description coverage, no output schema, and minimal annotations, the description is inadequate. It doesn't explain what happens after drawing (e.g., does it return an object ID?), coordinate systems, units, or how this interacts with other sketch operations. The context signals indicate significant gaps in documentation.

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 for 4 parameters, the description provides no parameter information beyond what's in the schema. It doesn't explain what 'radius', 'center_x', 'center_y', or 'center_z' mean in context, their units, or how they relate to the sketch coordinate system. The description fails to compensate for the schema's lack of descriptions.

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 a circle') and specifies the context ('in the most recent sketch'), making the purpose understandable. However, it doesn't explicitly differentiate from sibling drawing tools like 'draw_arc', 'draw_line', or 'draw_rectangle', which would require a 5.

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 minimal guidance by specifying 'in the most recent sketch', but offers no explicit when-to-use rules, alternatives, or exclusions compared to other drawing or geometry creation tools. There's no mention of prerequisites like needing an active sketch.

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