take_screenshot

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

No annotations are provided, so the description carries the burden. It discloses the basic behavior (captures primary display or window, returns PNG) but does not mention file size, permissions required, or whether it is a safe read-only operation. It adequately describes the core behavior without contradictions.

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 concise—two sentences that front-load the main action ('Captures a screenshot...') and then clarify the optional parameter behavior. Every sentence is necessary and well-structured.

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 tool with one optional parameter and no output schema or nested objects, the description is nearly complete. It could mention that the screenshot is of the primary display only (not multiple monitors) or specify resolution, but these are minor gaps.

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?

The schema covers the parameter fully (100% coverage). The description adds the important detail that window_title uses partial matching, which is not in the schema. This adds value beyond the schema.

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 captures a screenshot of the primary display or a specific window, and returns a PNG. It distinguishes between full-screen and window capture based on the optional parameter.

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 explains when to provide window_title (to capture a specific window) and when not (for full screen). No sibling tools exist, so no need for alternatives. It could be clearer on prerequisites or limitations, but it's adequate.

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