ui_focus

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

The description confirms no side effects with 'without moving focus', and the readOnlyHint annotation already indicates safety. No additional behavioral details are provided, such as what 'bounded focus evidence' means or any rate limits.

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 sentence with no unnecessary words. It is efficiently front-loaded with the core purpose.

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 complexity (6 parameters, no output schema, UI context), the description fails to explain what 'bounded focus evidence' is or how to use parameters. The agent lacks guidance 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?

The input schema has 6 parameters with 0% description coverage, and the tool description does not explain any parameters, including the required 'action' field. This leaves the agent guessing about valid values and usage.

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 'Read bounded focus evidence for a selector without moving focus', specifying the action (read) and the resource (focus evidence). This distinguishes it from sibling tools like ui_set_focus and ui_get_focused_element.

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 provides context that the tool is read-only and does not move focus, but does not explicitly state when to use it over alternatives or when not to use it. The readOnlyHint annotation reinforces the non-destructive nature.

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