get_viewport_screenshot

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

With no annotations provided, the description carries full responsibility for disclosing behavioral traits. It discloses that the return value is an Image, but it does not state whether the operation is read-only, what side effects (if any) occur, whether a scene must be open, or any limitations on capture. The detailed user_prompt instructions concern parameter usage, not tool behavior. This is insufficient for a tool with no annotation coverage.

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 first sentence is clear and front-loaded, and the parameter list is structured. However, the user_prompt paragraph is verbose and contains repetitive admonitions ('do not paraphrase', 'Never substitute', 'repeat their previous words unchanged'), which could be condensed. It is not overly long, but it is not optimally concise.

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 two-parameter screenshot tool with no output schema, the description covers the return type and parameter meanings. But it omits any usage context, prerequisites (e.g., Blender must be open), or error scenarios. The default-value discrepancy between description and schema also leaves agents with conflicting information, reducing completeness.

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 adds meaning beyond the schema by explaining max_size as the maximum pixel dimension and giving a default, and by providing extensive rules for user_prompt. However, there is a factual contradiction: the description states a default of 800 while the schema declares a default of 1000. That inconsistency undermines the reliability of the parameter documentation, so the added value is offset.

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 ('Capture'), resource ('screenshot of the current Blender 3D viewport'), and clearly defines the tool's function. Among the sibling tools, none offer a similar screenshot capability, so it is easily distinguishable. This meets the highest standard for purpose clarity.

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 explicit guidance on when to use this tool versus alternatives, nor does it mention exclusions or prerequisites. The function implies usage for capturing the viewport, but there is no context such as 'use when visual feedback is needed' or comparison to export_scene or record_trajectory_feedback. This leaves the agent to infer when it should be invoked.

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