browser_take_screenshot

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

Annotations already declare readOnlyHint=true and destructiveHint=false, covering safety. The description adds a key behavioral trait: the output is not interactive ('You can't perform actions based on the screenshot'), which is not captured by annotations. This adds meaningful context about the tool's limitations beyond the structured data.

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?

Two concise sentences with no redundant phrasing. The core purpose is stated first, followed by a critical limitation and alternative, maximizing informativeness per word.

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 read-only screenshot tool with comprehensive schema documentation and safety annotations, the description covers the essential decision points: when to use it and when not to. It doesn't explain return formats or error handling, but those are less critical given the tool's simplicity and the annotations' coverage.

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% with detailed descriptions for all 6 parameters. The description adds no parameter-specific information, and the baseline of 3 is appropriate since the schema fully documents parameters.

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?

States a specific verb ('Take') and resource ('screenshot of the current page'). Explicitly distinguishes from browser_snapshot by stating what it is not for ('You can't perform actions based on the screenshot'), making it clear which tool to use for captures vs. interactions.

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 explicit when-not-to-use guidance: 'You can't perform actions based on the screenshot' and directs to the alternative 'use browser_snapshot for actions'. This clearly routes an agent to the correct tool for interactive needs while implying this tool is for visual captures.

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