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

With no annotations provided, the description carries the behavioral disclosure burden. It states the capture mechanism (Windows APIs), the output format and rationale (downscaled JPEG to limit vision-token cost), and the relay behavior on secondary servers. This is meaningful context beyond the schema.

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?

Three concise sentences front-load the core purpose and immediately state the return type and cost rationale. Every sentence earns its place, and there is no redundant filler.

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 description covers the main inputs, output format, and expected behavior in multi-window and multi-server scenarios. A return value schema is absent, so mentioning the downscaled JPEG return is helpful, though the exact representation of the image data is not specified.

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 100%, so the schema fully documents both pid and maxWidth. The description repeats the 'provide pid when multiple windows are open' guidance and indirectly references maxWidth through the downscaling rationale, but does not add substantive new parameter semantics beyond the schema.

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 opens with a specific action and resource: capturing an actual OS screenshot of a Roblox window via Windows APIs. It clearly distinguishes this from in-game data or script-related tools by emphasizing the OS-level screenshot and JPEG return.

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 gives a concrete usage condition: provide pid when multiple windows are open. It also notes the relay behavior on secondary servers. While it does not explicitly name alternatives, no sibling tool performs OS screenshots, so the condition-based guidance is sufficient.

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