focus

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

With no annotations, the description carries the full burden. It only states 'Focus input at coordinates,' omitting behavioral traits like whether an element must exist, side effects, authentication needs, or what happens after focus.

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?

While the description is a single sentence, it is under-specified to the point of being unhelpful. Conciseness is not achieved when key information is missing.

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?

With no output schema and many sibling tools, the description fails to explain the tool's purpose adequately. It does not clarify what 'focus' means, leaving the agent without enough context for correct invocation.

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 coverage is 100%, so parameters are well-described in the schema. The description adds no extra meaning beyond the schema's existing definitions for 'x' and 'y' coordinates. Baseline score 3 applies.

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 'Focus input at coordinates.' names a verb and resource (focus input) but is vague. It does not specify whether it is focusing a UI element, setting cursor position, or something else. Distinguishing from siblings like 'click' or 'type' is not achieved.

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?

No guidance is provided on when to use this tool vs alternatives. No prerequisites, when-not-to, or context for choosing over siblings like 'click' or 'tap'.

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