puppeteer_screenshot

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

No annotations are provided, so the description must fully disclose behavioral traits. It mentions return format as base64 JPEG but omits important details such as whether it waits for full page load, the impact of delay and waitForSelector, viewport behavior, and any limitations (e.g., full-page screenshots, popups).

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: two sentences with no filler. The purpose and conditional use are front-loaded, making it efficient for an agent to parse.

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?

Given 6 parameters, no output schema, and sibling tools, the description is incomplete. It fails to explain the return format details (e.g., size limits), full-page vs viewport behavior, the role of delay/waitForSelector in execution, and how it differs from puppeteer_screenshot_debug or puppeteer_navigate + manual screenshot.

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%, so baseline is 3. The description only adds conditional logic for sessionId vs url, which is already implied by the parameter descriptions. No additional meaning beyond the schema is provided for other 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?

The description clearly states the tool takes a screenshot and returns base64 JPEG. It distinguishes between using an existing session (sessionId) vs navigating to a URL. However, it does not differentiate from the sibling tool puppeteer_screenshot_debug, which likely has a similar purpose.

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 provides guidance on when to use sessionId vs url. However, it lacks comparison with sibling tools (e.g., puppeteer_screenshot_debug, puppeteer_navigate) and does not specify prerequisites like needing an active session or URL validity.

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