browser_take_screenshot

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

Annotations already declare readOnlyHint=true and destructiveHint=false, so the description is consistent and adds the behavioral constraint that the screenshot cannot be used for interactive actions. This adds value beyond annotations, but doesn't elaborate on other traits like permission requirements or return behavior.

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 long with no superfluous information. It is front-loaded with the primary purpose and immediately provides usage guidance, making it efficient and easy to parse.

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 tool with 5 parameters (all fully described in schema) and no output schema, the description adequately covers purpose, usage, and differentiation. No additional explanation of return values is needed, as the tool is a simple capture.

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 parameters are well-documented in the schema. The description does not add additional meaning beyond what the schema provides, thus meeting the baseline for full 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 of the current page') and differentiates it from a sibling tool (browser_snapshot) by noting that the screenshot cannot be used for actions. This provides specific verb and resource scope, distinguishing it from alternatives.

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 explicitly tells when to use the tool (taking a screenshot) and when not to (for performing actions, use browser_snapshot instead). This provides clear context and alternatives, meeting the highest standard.

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