viewport_set_shading

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

The annotations mark this as non-read-only and destructiveHint=true, and the description does not contradict that. The description adds useful scope by specifying 'active viewport' rather than all viewports or scene data, which clarifies that the destructive hint refers to viewport UI state, not geometry or file content. It could still disclose more about persistence or side effects, but given the simple operation this is adequate.

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 compact and front-loaded: it states the operation, the target, and all valid values in two short lines. The bilingual format is organized and adds no unnecessary fluff, and every sentence earns its place.

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 single-parameter setter with a fully documented enum and no output schema, the description covers the essential information: what is changed, on what target, and with which options. It could include more usage context, but nothing critical for calling the tool correctly is missing.

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?

The input schema already documents the single 'mode' parameter with a full enum and a description. The tool description repeats the enum values but adds no new semantic detail beyond the schema, so the baseline score of 3 is appropriate.

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 states a specific verb (set), resource (active viewport), and property (shading mode), and enumerates all valid modes. This clearly distinguishes it from sibling viewport tools like viewport_set_view, viewport_set_layout, or viewport_capture, which concern different aspects of the viewport.

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 clearly implies the tool is used when the agent needs to change the active viewport's shading mode, and the mode list makes the scope obvious. However, it does not explicitly state when not to use it or mention alternatives among the viewport-related siblings, so the usage guidance is only implicit.

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