open_application

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

No annotations are provided, so the description must fully disclose behavior. It only states 'Launch or focus an application' without explaining what happens if the app is not found, whether it always focuses or launches, or any other behavioral traits (e.g., permissions, error handling).

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, front-loaded sentence with zero waste. Every word is necessary and contributes to the 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 simplicity (1 required param, no output schema), the description is adequate but misses edge cases like missing applications or multiple instances. With no annotations, it leaves the agent without guidance on error states or return values.

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 0%, so description must compensate. It adds meaning by stating 'by name' and giving examples, but lacks specifics on format (e.g., case sensitivity, exact vs. partial match). This provides basic guidance but is incomplete for precise 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?

Description uses specific verbs ('Launch or focus') and resource ('application'), with concrete examples ('Safari', 'Slack'). It clearly distinguishes from sibling tools like 'list_applications' and 'ax_click' which serve different purposes.

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 implies the tool is for launching or focusing an app by name, but does not explicitly state when to use it vs. alternatives (e.g., using 'list_applications' to find the correct name first). No exclusions or alternative suggestions are provided.

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