screenshot

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

No annotations are provided, so the description bears full responsibility. It discloses the output format (base64 PNG) and the keyless, direct capture behavior, but does not mention failure modes, page load handling, or limitations. This is minimal but not misleading.

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 three short sentences plus an Args list. Information is front-loaded, with the core purpose in the first sentence, and every phrase adds value. No filler or redundancy.

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 2-parameter screenshot tool with an output schema, the description covers core behavior, output format, and parameter semantics. It lacks some edge-case details (e.g., what happens on navigation failure), but is sufficient for the tool's simplicity.

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 coverage is 0%, so the description must compensate. The Args section explains both 'url' and 'full_page', with full_page's default clarified as 'visible viewport only'. It adds meaning beyond the raw schema, though the url explanation is slightly tautological.

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 'Take a screenshot of a webpage and return it as base64-encoded PNG' – a specific verb and resource with output format. However, it does not explicitly distinguish from sibling tools like 'snapshot' or 'pdf', so it lacks explicit sibling differentiation.

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 mentions it is 'Keyless' and navigates/captures directly, but it does not provide explicit when-to-use vs alternatives like 'snapshot' or 'get_content'. Usage is only implied by the purpose.

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