browser_take_screenshot

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

Annotations already declare this as a safe read-only, open-world operation. The description adds important context beyond annotations: the screenshot is visual output and cannot be acted upon, so agents must not confuse it with DOM/interaction data from browser_snapshot.

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 short sentences with the main purpose front-loaded and no wasted wording. The limitation and alternative are stated immediately after the purpose.

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 screenshot tool with rich schema coverage and safety annotations, the description gives enough guidance to select and invoke it correctly. The main minor gap is that it does not describe the return value or where the screenshot is saved, though the filename parameter hints at this.

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%, so the schema already documents all seven parameters, including format, scale, target, filename, and fullPage. The description adds no parameter-specific semantics, which is acceptable when the schema is this complete.

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 states a specific verb and resource: taking a screenshot of the current page. It also distinguishes the tool from its sibling browser_snapshot by explaining that screenshots cannot be used to perform actions, so an agent can route correctly without opening either schema.

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 gives a clear usage boundary: use browser_snapshot when you need to perform actions, and use this tool only to capture a screenshot. It does not explicitly state when to prefer full-page or element screenshots, but the core alternative is named.

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