browser_screenshot

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

The description reveals a conditional behavior: it may navigate to a new URL if provided, otherwise it uses the current page. It does not mention other side effects like cookie changes or history updates, and since no annotations are present, it carries the full burden of transparency, resulting in a moderate score.

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 two sentences, directly to the point, with no unnecessary words. It efficiently communicates the core function and the conditional behavior, making it highly concise and well-structured.

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?

It covers the main use cases (opening a URL or screenshotting current page) and mentions the output format (PNG). It lacks details on error handling or specific behavior of waitMs/fullPage, but given the simple nature of the tool, it is reasonably complete.

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 schema already includes descriptions for all three parameters (url, waitMs, fullPage). The tool description adds little beyond repeating the meaning of url; it does not add new information about waitMs or fullPage, so it stays at the baseline given the high schema coverage.

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 function: take a screenshot, optionally after opening a URL. It also clarifies the behavior when a page is already open via the conditional phrase. However, it does not explicitly differentiate it from sibling tools like screenshotElement, but the mention of 'current page' and 'PNG' provides implicit distinction.

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?

Provides basic guidance: if a page is already open, it screenshots the current one; otherwise, it can open a URL first. It does not explicitly name alternatives or conditions for when to use this tool over others, but the conditional note gives a practical usage pattern.

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