screen_capture

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

Annotations already declare readOnlyHint=true, and the description adds minimal context with 'validated' and 'selected device'. However, it fails to disclose what happens to the captured screenshot (e.g., returned path, whether it's automatically saved), so additional behavioral context is missing.

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, well-structured sentence with no redundant or superfluous words. It conveys the core purpose efficiently.

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 capture tool, the description covers the basic function but omits key operational details such as parameter semantics, return value, and whether the screenshot is automatically saved. This is adequate but leaves gaps for an agent to function autonomously.

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?

With schema description coverage at 0%, the description does not explain the parameters 'label' or 'save_to_evidence'. The agent must infer their meaning solely from names, which may lead to incorrect usage.

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 a specific verb ('Capture') and resource ('validated PNG screenshot') with a context ('from the selected device'). This unambiguously distinguishes it from sibling tools like ui_dump or screen_tap.

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 usage is implied (when a screenshot is needed), but there is no explicit guidance on when to use this tool versus alternatives, nor any exclusion criteria. The description doesn't mention prerequisites like requiring a selected device.

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