Capture a screenshot of a web page

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

Annotations are present (readOnlyHint=false, openWorldHint=true, idempotentHint=false, destructiveHint=false) and the description does not contradict them. Beyond the annotations it adds real context: pages must be public, capture runs in a headless browser, output may be a link or an inline image depending on size. It omits any mention of rate limits or failure modes for unreachable pages.

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?

Two sentences, front-loaded with the mechanism and output, then the use case. No filler, and the return behavior is stated before the softer suitability note. Tight and readable.

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 14-parameter tool with no output schema, the description covers the essentials: public-page constraint, headless-browser execution, supported formats, and the dual return shape (link vs inline image). The PDF-specific and viewport parameters are left entirely to the schema, which is acceptable given 100% coverage.

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% across all 14 parameters, so the schema already documents url, format, delay, dimensions, and the PDF-only fields in detail. The description only restates the format choices (JPEG/PNG/WebP/PDF) already enumerated in the schema, adding no meaning beyond it. Baseline 3 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?

States a specific verb and resource: loads a public web page in a headless browser and captures it as an image or PDF. Clear enough to act on, but it never differentiates itself from closely related siblings like render_html, read_webpage, convert_html_to_markdown, or preview_link, which an agent must disambiguate among.

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?

"Suited to checking how a page renders or keeping a visual record of it" implies the use case but gives no explicit when-to-use-vs-alternative guidance. With render_html and read_webpage as siblings, the agent is left to infer which tool applies to a given page-inspection task.

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