3D-MCP

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

With no annotations, the description carries full burden but lacks behavioral details. It doesn't disclose whether this is a destructive mutation (likely, given 'transform'), what permissions are needed, how errors are handled (e.g., invalid vertex IDs), or the expected output format. The description implies a write operation but provides no safety or operational context.

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 with no wasted words. It's front-loaded and directly states the tool's function, making it easy to parse quickly, though this conciseness comes at the cost of detail.

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 complex mutation tool with no annotations and no output schema, the description is incomplete. It doesn't explain the transformation's effect (e.g., overwriting vs. adjusting UVs), error conditions, or return values, leaving significant gaps for the agent to navigate without structured support.

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 parameters are fully documented in the schema. The description adds no additional meaning beyond the schema's details about UV channels, mesh IDs, and vertex transformations, meeting the baseline for high schema coverage without extra value.

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 'Transform UV coordinates for vertices' states the action and target, but is vague about scope and mechanism. It doesn't specify whether this applies to selected vertices, all vertices, or specific meshes, nor does it distinguish from sibling tools like 'transformVertices' or 'unwrapUVs' which might handle different transformations.

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?

No guidance is provided on when to use this tool versus alternatives. The description doesn't mention prerequisites (e.g., existing UV maps), exclusions, or compare it to similar tools like 'transformVertices' (for 3D coordinates) or 'unwrapUVs' (for UV unwrapping), leaving the agent to infer usage from context alone.

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