set_render_performance

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

With no annotations present the description must carry the full burden, and it does disclose the important behaviours: only supplied fields change, Simplify must be enabled for max_subdivision and texture settings to take effect, and some settings are Cycles-only. It does not say whether changes persist to the saved file, whether the render engine must already be Cycles, or whether these affect all scenes.

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 goal is front-loaded and the Args block is one line per parameter with no filler; every sentence carries information. It is longer than average for a setter, but the length is justified by eight undocumented parameters.

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 an eight-parameter mutation tool with no annotations, the definition covers purpose, partial-update semantics, per-parameter ranges and the cross-parameter dependency. Return values are already covered by an output schema, so restating them is harmless redundancy rather than a gap; only engine prerequisites and persistence behaviour are unstated.

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 0%, so the description must define all eight parameters, and it does: each is named with its meaning, its valid range (0-6 subdivision, 8-8192 tile size, 0.0-1.0 texture resolution, OFF or 128-8192 texture limit), and a dependence note tying simplify to the texture settings. This is well beyond what the bare schema offers.

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 opening line states the goal ('speed up heavy renders or fit them in memory') rather than an explicit verb+resource, but the Args block makes unmistakable that this tool sets render performance options such as simplify, tile size and texture limits. It does not distinguish itself from adjacent render tools like set_render_samples or set_cycles_sampling, so an agent must infer the boundary from the parameter list.

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?

'Speed up heavy renders or fit them in memory' gives clear situational context for when to reach for this tool, and 'Leave anything unset to keep it' tells the agent it is a partial-update operation, which is critical guidance. There are no explicit exclusions or pointers to the sibling tools that cover samples, denoising or light paths.

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