open_app

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

Annotations indicate non-read-only (readOnlyHint: false). Description says launch/activate, consistent with modification. However, no additional behavioral details like foreground behavior, error handling, or permissions required.

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?

One sentence, efficient and front-loaded. No unnecessary words. Could include a brief note on failure behavior but overall concise.

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?

Tool is simple but lacks details on return value, error cases, and behavior when app is not found. With no output schema, description should cover what the tool returns or indicates on success/failure.

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 has 0% coverage for the single parameter 'name'. Description adds 'by name (e.g. Safari)', providing a basic example. It does not specify whether it expects display name, bundle ID, or path, so partial improvement.

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 launches/activates an application by name, with an example (Safari). It distinguishes from sibling tools like close_app and list_running_apps.

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 explicit guidance on when to use this vs alternatives like open_url or run_applescript. It is implied for launching apps by name, but lacks context about prerequisites or exclusions.

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