take_screenshot

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

With no annotations provided, the description carries full burden. It mentions returning base64 image data but also includes an output_path argument for saving, creating ambiguity. It does not disclose permissions, overwrite behavior, or other side effects.

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 brief with a clear purpose sentence, return format statement, and parameter list. It is front-loaded with the core action, and every sentence adds value. However, it could be slightly more 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?

Given the tool's simplicity (1 param, no annotations, but has output schema), the description covers the basic purpose and return type. However, it lacks details on behavior like whether it saves to file or just returns base64, and any constraints like orientation or permissions.

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 0%, so description must compensate. It states 'output_path: Where to save the screenshot file,' adding basic meaning but missing details on optionality, default value, or format. This is minimal value added.

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 'Take a screenshot' and the resource 'current phone screen', and it distinguishes itself from sibling tools like 'take_photo' or 'dump_ui' by focusing on screen capture.

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 usage (when you need a screenshot) but provides no explicit guidance on when to use it over alternatives or any prerequisites. There are no exclusions or alternative tool mentions.

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