screenshot

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

Without annotations, the description carries full burden. It discloses the output format (JPEG), downscaling behavior, and the effect of parameters (save to disk at full res, return full resolution). It does not explicitly state it is non-destructive, but this is implied. Beyond that, it provides sufficient detail for safe use.

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 short paragraphs and no extraneous information. Every sentence contributes to understanding the tool's core function and parameters. It is front-loaded with the main action.

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 the tool's low complexity (2 params, no output schema), the description covers basic usage but omits details about the return format (e.g., base64 image data) and how to process the result. Without an output schema, users need more context about what the tool returns.

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 is the sole source of parameter meaning. It explains 'save_path' as optional path to save to disk at full resolution, and 'full_resolution' as returning without downscaling. This adds significant value beyond the schema's property names and types.

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 it screenshots the page as a JPEG, downscaled to max 1024px wide. It specifies the format and default behavior, making the tool's primary purpose unambiguous and distinguishing it from siblings like start_screencast.

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 does not provide any guidance on when to use this tool versus alternatives (e.g., start_screencast for video, export_screencast_mp4). There is no mention of prerequisites, limitations, or context in which it is appropriate.

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