app_start

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

No annotations are provided, so the description carries the burden of behavioral disclosure. It does reveal the idempotent behavior (returns silently if running) and the side effects of downloading Electron.js and Uindow. However, it doesn't mention whether downloads require network access, what failures look like, or how long launch may take, leaving meaningful gaps.

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 compact at three lines and front-loads the core purpose. Each sentence earns its place: the purpose, the idempotent behavior, and the side-effect steps. The typo 'Uindow' costs a point from perfect structure.

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 parameters, no output schema, and no annotations, the description must fully explain the tool. It covers the essential start/launch logic and dependency download, but omits return behavior, potential failure modes, and network requirements. For a side-effecting tool like this, additional context on what the return value or expected outcomes would be valuable.

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 has zero parameters, and schema coverage is 100% (there are no parameters to document). With 0 params, the baseline is 4 per the rubric, and the description correctly doesn't invent parameter details. This is appropriate for a parameterless tool.

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 starts an application ('Start application'), with specific verb+resource. It distinguishes from siblings like app_docs, app_stop, app_status by focusing on the launch action. However, 'Uindow' appears to be a typo for 'Window' which slightly diminishes clarity.

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 explains the conditional behavior (if already running, return silently; otherwise download dependencies and launch). This gives some guidance on when it's a no-op vs. active, but doesn't explicitly contrast with sibling tools like 'start' or 'app_status' or explain prerequisites beyond the download step.

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