Get Screen Size

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

No annotations are provided, so the description must handle behavioral disclosure. It clarifies the output (width and height in pixels) but does not mention if the device must be connected or any potential errors (e.g., device not found). The mutability aspect is clear: it's a read operation.

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: two sentences that clearly state purpose and output. No wasted words.

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?

The description is complete for a simple read tool with one parameter and no output schema. It explains the purpose and return values. Could mention error conditions (e.g., device not connected) but overall sufficient.

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 100% (device_id documented). The description does not add additional meaning beyond the schema, which is fine when coverage is high. Baseline 3 is appropriate.

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 uses specific verb+resource: 'Get the screen resolution of a connected Android device. Returns the width and height in pixels.' It clearly states what it does and distinguishes from siblings like take_screenshot or analyze_screen.

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 states when to use it (to get screen resolution), but provides no guidance on when not to use it or alternatives. Siblings like analyze_screen could be related but no exclusions are mentioned.

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