3D-MCP

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

With no annotations provided, the description carries full burden for behavioral disclosure but provides none. It doesn't indicate whether this is a read or write operation (though 'create' implies mutation), what permissions might be required, whether it's destructive to existing data, what happens on failure, or what the return value might be. For a creation tool with complex parameters, this lack of behavioral context is severely inadequate.

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 extremely concise at just two words, which could be appropriate if it were more informative. However, this brevity comes at the cost of being under-specified rather than efficiently informative. It's front-loaded with the core action but lacks necessary context. While not verbose or poorly structured, it's too minimal to be truly effective.

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 no annotations, no output schema, and complex nested parameters (though well-documented in schema), the description is completely inadequate. It doesn't explain what Joints are, what creation entails, what happens after creation, error conditions, or any behavioral aspects. The agent must rely entirely on the schema and tool name inference, which is insufficient for safe and effective tool invocation.

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%, so the schema fully documents the single 'items' parameter and all its nested properties. The description adds no parameter information beyond what's already in the schema - it doesn't explain what constitutes a valid Joint, provide examples, or clarify relationships between parameters. With complete schema coverage, the baseline score of 3 is appropriate as the description doesn't add value but doesn't need to compensate for gaps.

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 'Create multiple Joints' is a tautology that merely restates the tool name 'createJoints' with the addition of 'multiple'. It doesn't specify what Joints are in this context (3D modeling joints, mechanical joints, etc.) or what 'create' actually does (adds to scene, generates in database, etc.). While it distinguishes from deletion tools by being a creation tool, it doesn't differentiate from other creation tools like 'createIKChains' or 'createConstraints' beyond the resource name.

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 absolutely no guidance on when to use this tool versus alternatives. It doesn't mention when to use createJoints versus createIKChains (which might be related), when to use batch creation versus single creation (if such a tool exists), or any prerequisites like needing a scene context. The agent must infer usage purely from the name and schema.

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