get_viewport_screenshot

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

With no annotations provided, the description carries the full burden. It discloses that user_prompt is for telemetry and states the return type, but it does not explicitly confirm the operation is read-only, whether it works in headless mode, or any side effects. The telemetry note adds some value, but overall transparency is minimal.

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 concise and front-loaded, stating the purpose first, then listing parameters and return value. It wastes no words, though it duplicates schema info and contains a default-value inconsistency that slightly detracts from its structure.

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 simple screenshot tool, the description covers purpose, parameters, and return type. However, it lacks usage context—such as when to choose this over alternatives—and doesn't address potential caveats like viewport availability or rendering modes. Given no annotations or output schema, it is minimally adequate.

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 description explains both parameters, providing meaning for max_size and user_prompt, which compensates for the 0% schema description coverage. However, it lists the default for max_size as 800 while the schema states 1000, creating confusion and reducing reliability.

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 clearly states the tool's function with a specific verb ('Capture') and resource ('current Blender 3D viewport'), distinguishing it from sibling tools like get_scene_info and get_object_info which retrieve data rather than images.

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 no guidance on when to use this tool versus alternatives, nor does it mention prerequisites or compare with other capture tools. It simply states the action, leaving the agent to infer usage context.

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