Take Screenshot

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

With no annotations provided, the description must carry the burden of disclosing behavioral details. It only states the action without revealing whether it captures the viewport or full page, whether it saves to the 'path' parameter or returns image data, or whether it blocks until the page is stable. The description adds no behavioral context beyond the bare operation.

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 short sentence, which is structurally concise and front-loaded. However, it is so sparse that it borders on under-specification, lacking any detail that would aid the agent. It earns a middle score for being appropriately brief but not sufficiently informative.

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?

This is a simple tool, but the description omits crucial context such as the need for an existing session (implied by the required sessionId), the behavior of the optional path parameter, and the nature of the output (there is an output schema, but the description doesn't mention how the screenshot is delivered). The description is incomplete for an agent to safely invoke the tool without additional information.

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 two parameters (sessionId, path) with 0% schema coverage (no descriptions in the schema). The tool description does not mention either parameter, leaving the agent without any semantic understanding of 'path' (e.g., is it a file path to save the screenshot?) or how 'sessionId' relates to the current page. The description fails to compensate for the missing schema descriptions.

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 action ('Take a screenshot') and the resource ('current page'), making the tool's purpose immediately obvious. It distinguishes itself from sibling tools like browser.snapshot by specifying a screenshot (visual capture) rather than a DOM snapshot or text extraction.

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 regarding when to use this tool versus alternatives. There is no mention of prerequisites (e.g., active page, loaded session) or exclusions, leaving the agent to infer usage from context alone.

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