capture_screen

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

With no annotations, the description must disclose behavioral traits. It mentions the output destination but omits details about directory creation, file overwriting, the role of the 'label' parameter, and failure behavior. This leaves the tool's behavior largely unspecified.

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 a single sentence that front-loads the verb and resource, with no unnecessary words. It is concise and clearly 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?

Despite the tool's simplicity, the description is incomplete for invocation: it fails to explain the 'label' parameter, what the tool returns (e.g., a file path), and any preconditions or error handling. The lack of output schema and annotations increases the need for description detail, which is absent.

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 defines a single optional 'label' parameter with no description (0% coverage), and the description does not mention 'label' at all. An agent has no information about how this parameter affects the capture or output.

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 verb 'Capture' and the resource 'current primary screen', along with the output ('save a PNG under ./captures'). This differentiates it from sibling tools that handle macros, diagnostics, and terminal commands.

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 implies its usage by stating the action, but it does not explicitly say when to use it or mention alternatives. There is no context about prerequisites like screen recording permissions or scenarios where this tool is preferred.

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