screen_info

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

With no annotations and no output schema, the description carries the burden of explaining behavior. It does disclose the informational nature of the tool and the specific output fields (resolution, position, scale factor, visible area), which implies a read-only operation. However, it does not describe return format, data types, or any edge cases like disconnected or mirrored displays.

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 that front-loads the action and resource, then lists the key return fields. Every word adds value and there is no redundancy.

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, parameterless information-retrieval tool, the description covers the main purpose and the expected output categories. Because there is no output schema and no annotations, listing the return fields is helpful. It could be slightly more complete by specifying the return format, but the tool's simplicity keeps the gap small.

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 tool has zero parameters and the schema properties object is empty, so there is no parameter ambiguity to clarify. The description fully covers the tool's interface by indicating what data will be returned. This matches the baseline for parameterless tools.

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 states a specific verb ('Get information') and a clear resource ('all connected displays/screens'), and enumerates the kind of data returned (resolution, position, scale factor, visible area). It does not explicitly contrast itself with siblings like ai_screen_context, but the scope is unambiguous enough for an agent to identify what this tool does.

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?

There is no guidance on when to choose this tool over alternatives such as screenshot, window_list, or ai_screen_context. The intended context is only implied by the description itself: when display/screen metadata is needed. No explicit exclusions or alternative-routing information is provided.

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