screen_shot

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

No annotations provided, so description carries burden. It mentions dependencies (pymobiledevice3, optional Pillow) and return type (image+meta), but does not disclose whether the tool is read-only or has side effects. Acceptable for a screenshot tool but could be more detailed.

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?

Concise single paragraph of ~40 words. Every sentence adds value: purpose, usage guidance, alternative, requirements, return type. No fluff, front-loaded with key information.

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?

Completes most needs: explains purpose, usage, dependencies, and return. Lacks detail on meta return and udid parameter, but overall sufficient for a simple tool with 2 parameters.

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 50% (only quality has description). The tool description adds no additional meaning to parameters; udid is unexplained and quality lacks context beyond schema. Does not compensate for missing schema descriptions.

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 is a pixel screenshot via lockdown ScreenshotService, distinguishing itself from Accessibility and Frida UI dump. It also mentions preferring screen_snapshot for tap refs, differentiating from sibling tools.

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?

Explicitly states when to use (texts sparse/visual layout unclear) and when not to (prefer screen_snapshot for tap refs), providing clear context and an alternative tool.

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