set_render_engine

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It only states the action ('set') without revealing consequences (e.g., whether it overrides existing settings, requires specific permissions, or has side effects). The lack of detail about the operation's effects makes it inadequate for a mutation tool.

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 short, which is conducive to conciseness, but it is so under-specified that it provides virtually no useful information. While it is front-loaded and free of fluff, the brevity works against clarity. It earns a mid-range score because it avoids verbosity but fails to deliver substance.

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?

The tool is simple (one parameter) and an output schema exists, but the description still omits essential context: valid engine values, effects on the scene, or any relationship to sibling tools. Without annotations or parameter explanations, an agent cannot reliably invoke this tool correctly. The completeness is poor given the lack of supporting detail.

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 schema has one required parameter 'engine' with no type, description, or enums, and schema description coverage is 0%. The description does not compensate at all—it fails to explain what values 'engine' accepts (e.g., 'CYCLES', 'BLENDER_EEVEE') or the expected format. This is a critical gap for a parameter-driven tool.

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 'Set the render engine' uses a specific verb (set) and a clear resource (render engine), stating the core action unambiguously. However, it does not distinguish itself from similar siblings like set_render_settings or set_viewport_shading, so it falls slightly short of a perfect score.

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?

There is no guidance on when to use this tool versus alternative tools. No mention of context, prerequisites, or situations where a different command would be more appropriate. The description is a bare statement with no usage direction.

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