render_screenshot

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

With no annotations, the description carries the behavioral burden and does so well: it discloses that rendering happens in a separate GUI session, that human draft state and scroll position are not shared, and that passing a path navigates before capture. Minor omissions like rendering completion or failure behavior remain, but the core side-effect profile is clear.

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?

Three short sentences with no filler: the first states the main action, the second warns about state isolation, and the third explains the optional path. All sentences earn their place.

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 tool with one optional parameter and no output schema, the description is largely complete: it covers output type, state isolation, and path handling. It could mention what happens when path is omitted or how rendering relates to document state, but the essentials are present.

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% for the single optional path parameter, and the description adds value by explaining that the path is a GUI-interpreted URL taken as-is and that providing it moves to that screen before capturing. This goes beyond the schema's default and example.

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 the exact function: returning a PNG rendered in a separate GUI session for the same document. It clearly distinguishes this from siblings like read_blob or gui_url by focusing on rendering and pixel output rather than data or URL operations.

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?

It gives clear context on when the tool should be used (to get a rendered PNG of the document) and explains the path parameter's navigation behavior. It does not explicitly name alternative tools or exclusion cases, but the separate-session and path semantics provide adequate usage guidance.

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