emergent_screenshot_preview

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

Without annotations, the description carries the behavioral transparency burden. It usefully discloses the Playwright dependency and that it is installed automatically, which helps an agent anticipate setup. However, it does not mention whether the tool returns file paths, whether it performs network requests, or how failures are surfaced.

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 sentences, both useful: the first front-loads the core behavior and viewport scope, the second adds a relevant prerequisite. There is no filler or redundancy.

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 relatively simple screenshot tool, the description covers the main purpose, viewport options, and an important runtime prerequisite. Since there is no output schema, it could mention what the tool returns or that screenshots are saved to outputDir, but the available schema and description are sufficient for basic invocation.

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 the schema already documents all three parameters. The description adds context about the viewport names but does not provide additional parameter-level meaning beyond what the input schema already offers.

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 states a specific action ('Take screenshots'), a clear resource ('the live preview'), and a specific scope (multiple viewport sizes: phone, tablet, laptop, TV). This clearly distinguishes it from sibling tools like emergent_get_preview, which is about retrieving preview information rather than capturing images.

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 intended use is implied: use this tool when screenshots of a live preview at various viewport sizes are needed. However, the description gives no explicit guidance on when to prefer this over alternatives or when not to use it, and the sibling tool emergent_get_preview is not contrasted.

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