playwright_screenshot

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

With no annotations, the description carries the full burden of disclosure. It adds valuable behavior: filename sanitization, .png enforcement, and containment to ~/Downloads. It does not specify whether the screenshot captures the viewport or full page, which is a common behavioral expectation, but the disclosed safety trait is significant.

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: the first is a concise main action, and the second adds a critical constraint. There is no redundant information or filler.

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 simple single-parameter tool with an output schema, the description provides enough context. It covers the action, destination, return value, and safety behavior. It lacks edge-case details (e.g., overwrite behavior, waiting for page load), but these are less critical given the output schema and straightforward purpose.

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 0%, so the description must compensate. It indirectly references the 'name' parameter by discussing filename sanitization, but it never explicitly says that the 'name' parameter controls the output filename. The schema's default value hints at it, but the description should have explicitly linked the parameter to its function.

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 action (Save a screenshot), the target resource (current page), the destination (~/Downloads), and the return (path). It distinguishes itself from sibling tools like playwright_record or playwright_navigate by being specifically about screenshots.

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 phrase 'current page' conveys the appropriate context for use. It does not explicitly mention when not to use it or compare with alternatives, but its purpose is clear enough that an agent would know to use it when a static screenshot is needed. A nudge toward alternative tools (e.g., playwright_record for video) would improve it to a 5.

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