browser_take_screenshot

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

Without annotations, the description carries the burden of disclosing behavioral traits. It adds a key limitation (screenshots are not actionable) and points to an alternative, which is valuable. It does not mention other behaviors like file storage or permissions, but these are either implied by the tool's name or covered by the schema.

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 that immediately state the purpose and include a useful warning. There is no redundant or extraneous content; every word earns its place.

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?

The rich schema covers all parameters and behaviors like fullPage and element screenshots. The description adds the critical distinction from browser_snapshot and notes the non-actionable nature of screenshots. While return formatting isn't described, it's straightforward for a screenshot tool, making the overall definition complete enough.

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 provides 100% coverage with detailed descriptions for all parameters, including enums and defaults. The tool description itself does not add parameter-specific details, so a baseline score of 3 is appropriate given the schema handles parameter semantics.

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') with a specific verb and resource. It also distinguishes itself from the sibling tool browser_snapshot by noting screenshots cannot be used for actions, which clarifies its unique role.

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 the agent when not to use this tool ('You can't perform actions based on the screenshot') and directs to the appropriate alternative ('use browser_snapshot for actions'). This provides clear contextual guidance for tool selection.

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