wrave_take_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. The description mentions output format (base64 PNG/JPEG) and scope options (viewport or full page via full_page parameter), which adds value. However, it doesn't disclose potential side effects (e.g., does it affect the tab's state? Does it require the tab to be visible?), or the actual size/resolution of the screenshot. For a read-only capture tool, the lack of side-effect disclosure is less critical, but some behavioral context like 'returns a base64 string' is implicit in the description, so it's adequate 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?

The description is a single, efficient sentence that front-loads the core purpose and mentions key options. It has zero fluff, and every word earns its place. It clearly states the output format and scope options, which are critical for agent decision-making.

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 relatively simple tool with three parameters awaits and no output schema, the description is mostly complete. However, it doesn't mention the tab_id parameter (though that's obvious from name), nor does it specify the return structure (just says base64 PNG/JPEG). It lacks details on error conditions (e.g., invalid tab_id) or the impact on the tab (e.g., does it scroll the page?). Given the tool's simplicity, a 3 is reasonable; it covers the essentials but leaves minor gaps.

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 only 33% (only tab_id has a description). The description names 'viewport or full page' which aligns with the full_page parameter, and 'PNG/JPEG' aligns with the format enum. This adds meaning beyond the bare schema. However, it doesn't explain the behavior of the format parameter (e.g., trade-offs) or the default behavior of full_page (false means viewport). Since the description partially compensates for the low coverage, a 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?

The description clearly states the tool's purpose: 'Capture a screenshot of the tab viewport or full page as base64 PNG/JPEG.' It specifies the action (capture), the resource (tab viewport or full page), and the output format (base64 PNG/JPEG). This distinguishes it from siblings like wrave_list_tabs or wrave_get_dom_tree, which have different purposes.

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 when to use this tool (when you need a visual screenshot of the page), but it does not explicitly state when not to use it or mention alternatives. For example, it doesn't say 'use wrave_get_snapshot for text-based representation'. The context signals show a rich tool set, but the description alone doesn't guide the agent away from alternatives. So it's clear but lacks explicit exclusions.

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