Capture an Android display

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

Annotations indicate it's not read-only, and description adds internal resolution step. However, it does not clarify artifact creation, error handling, or permission requirements. Annotations balance the safety profile.

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 very concise (one sentence, 12 words) and front-loaded with action and resource. It could be slightly expanded with a use-case note without becoming verbose.

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?

Covers core purpose but lacks details about saveArtifact, error scenarios, and use-case guidance relative to siblings. Output schema handles return values, so completeness is adequate for this simple tool.

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 description adds meaning to displayId by explaining the resolution to physical ID. Schema already covers serial and displayId well, but saveArtifact is unexplained. Description compensates partially for moderate schema coverage (67%).

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 action (capture) and resource (one logical display), with technical nuance about resolving SurfaceFlinger physical display ID. It distinguishes from siblings like mobile_screen_record and mobile_displays_list.

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 provides no guidance on when to use this tool versus alternatives like mobile_screen_record or mobile_displays_list. It does not mention prerequisites or context for use.

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