Take a Ryubing screenshot

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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering the safety profile. The description adds the 'without desktop window chrome' scoping but does not disclose how the screenshot is returned (e.g., file path, base64) or any side effects. With annotations covering safety, this is acceptable but not rich.

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?

A single, front-loaded sentence with no waste. 'Capture the emulator's rendered game frame without desktop window chrome' is specific and succinct, earning every word.

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 defines what is captured but omits details about the return value or output format, which is critical since no output schema exists. It also lacks explicit usage guidelines. Given the simple optional parameters and strong annotations, it is minimally adequate but has a clear gap on return behavior.

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 input schema covers 67% of parameters with descriptions (quality, sessionId), while format lacks a description. The tool description adds no parameter-specific context, relying on the schema. At the high schema coverage baseline, this is appropriate.

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 uses the specific verb 'Capture' with the resource 'the emulator's rendered game frame' and adds the scope 'without desktop window chrome,' clearly distinguishing it from less specific screenshot tools. There are no competing siblings, so the purpose is unambiguous.

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 implies usage for capturing pure gameplay visuals ('without desktop window chrome') but does not explicitly state when to use it, when not to, or mention alternatives. Sibling tools do not include another screenshot tool, so the guidance is minimal but not misleading.

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