screenshot_page

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

The annotation readOnlyHint=true already signals a safe read operation. The description adds the specific return format (base64 PNG), which is helpful context. However, it does not disclose behavior when saveTo is set, such as whether a file path is returned or whether the output is no longer base64 in that mode.

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, front-loaded sentence that states verb, resource, and format with no filler or redundant content. Every word earns its place.

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 tool is simple, but there is no output schema and the description only covers the default base64 return. It does not clarify what the response contains when saveTo is provided, even though the parameter schema explains the file-saving side. With no output schema, the description should have compensated for this gap.

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%, with the single saveTo parameter fully described in the input schema. The description adds no additional parameter detail, but the schema carries the burden, so the baseline 3 applies.

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?

Description uses the specific verb 'Capture' with resource 'page screenshot' and output format 'base64 PNG'. It clearly distinguishes from sibling tools like screenshot_by_uid, which targets an element (UID) rather than the whole page.

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?

No guidance is provided about when to use this tool versus siblings like screenshot_by_uid or take_snapshot. It does not mention prerequisites, exclusions, or preferred contexts, so the agent is left to infer usage from the name and schema.

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