capture_screenshot

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. It mentions 'if supported', hinting at limitations, but does not specify what those limitations are (e.g., platform restrictions, element visibility). It fails to describe critical behaviors such as output format (e.g., image data, file path), error handling, or side effects (e.g., whether it pauses execution). This is inadequate for a tool with potential visual and system interactions.

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 a single, efficient sentence that directly states the tool's function. It is front-loaded with the core action ('Capture screenshot of an element') and includes a qualifier ('if supported') that, while vague, is concise. There is no wasted verbiage, making it structurally sound.

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?

Given the complexity of a screenshot tool (involving visual capture and potential system dependencies), the description is incomplete. With no annotations and no output schema, it fails to explain the return value (e.g., image data, success status) or behavioral details like permissions or side effects. The schema covers the parameter, but overall context is lacking for effective use.

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 has 100% description coverage, with the 'id' parameter documented as 'Element ID'. The description adds no additional meaning beyond this, such as explaining what constitutes a valid ID or how to obtain it. Since schema coverage is high, the baseline score of 3 is appropriate, as the description does not compensate but also does not detract.

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 the tool's purpose as capturing a screenshot of an element, which is clear but vague. It does not specify what type of element (e.g., UI component, web element) or in what context (e.g., browser, application), and it does not distinguish from sibling tools like 'highlight_element' or 'scroll_to_element' that might involve visual interactions. The phrase 'if supported' adds uncertainty but does not clarify the scope.

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. It does not mention prerequisites (e.g., needing a connected element or specific state), exclusions (e.g., unsupported element types), or related tools like 'get_element_by_id' for identifying elements. The lack of context leaves usage unclear.

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