playwright__browser_take_screenshot

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

Annotations already indicate readOnlyHint=true and destructiveHint=false, so the description adds value by stating 'You can't perform actions based on the screenshot,' which is a behavioral limitation beyond the annotation. However, it does not disclose other traits like the screenshot being a static capture or the handling of dynamic content.

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 extremely concise with two sentences, each serving a distinct purpose: stating the action and providing a critical usage limitation. No unnecessary words, and the key information is front-loaded.

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?

Despite having 6 parameters and no output schema, the description does not explain what the tool returns (e.g., file path, base64 data) or how to interpret the output. It also lacks guidance on parameter usage (e.g., when to use fullPage, target, or element). The agent is left without critical context for a tool with moderate complexity.

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 coverage is 100%, and all parameters are well-described in the input schema. The description adds no additional parameter-level information, so the baseline score of 3 is appropriate.

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 'Take a screenshot of the current page,' specifying the verb and resource. It also distinguishes from the sibling tool 'browser_snapshot' by noting that actions cannot be based on the screenshot, effectively differentiating the two tools.

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 advises against using this tool for actions and directs to 'browser_snapshot' as an alternative. However, it does not provide guidance on when to use this tool (e.g., for visual inspection, documentation) or exclude other scenarios, leaving room for ambiguity.

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