ax_focus

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

Without annotations, describes key behaviors: background operation, no cursor movement, query matching, target selection (last window-captured app), and error handling on Windows. Missing success/failure details for macOS.

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?

Three concise sentences, each adding distinct value: action, platform constraints, query behavior. 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?

Given no output schema, annotations, and one parameter, the description covers purpose, platform, target selection, and query matching. Could mention behavior on multiple matches, but adequate for a simple tool.

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% with clear description for 'query'. The tool description adds no new information about the parameter beyond what the schema already provides.

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 tool moves keyboard focus via the OS accessibility tree, with specific verb 'move' and resource 'control'. It distinguishes from siblings like ax_click (click) and dump_ax (dump tree) by focusing solely on focus manipulation.

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?

Provides context on when to use: background, no cursor, native-app accessibility only, and platform limitations (macOS vs Windows). Does not explicitly state when not to use but implies constraints.

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