mc_screen

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

With no annotations, the description carries the full behavioral burden, and it does disclose the return content (widget labels plus GUI coordinates), which is the essential behavior for a listing tool. It omits failure/empty behavior (e.g., what is returned when no GUI is open) and whether coordinates are absolute screen coordinates or widget-relative.

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?

A single compact sentence front-loads what is listed and follows with the return payload and the companion tool. Every clause earns its place with 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 parameterless read-only tool with no output schema, the description supplies enough to call it correctly: what it enumerates and what fields come back. The only meaningful gap is the absence of a note on behavior when no screen/GUI is active.

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 takes zero parameters and the schema is an empty object, so there is no parameter semantics to add; the baseline of 4 applies. The description correctly implies no input is required.

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 gives a specific verb and resource ('List widgets on the current Minecraft screen') and states the payload ('labels and GUI coordinates'), which separates it from siblings like mc_screenshot or mc_inventory. It stops short of explicitly contrasting itself with those siblings, so it is clear but not maximally differentiated.

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?

'use with mc_click_widget' implies the workflow (enumerate widgets, then click one) and names the consuming sibling, which is useful. However, it never states when to prefer this over mc_screenshot or what to do if no screen is open, so the guidance is implied rather than explicit.

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