open_app

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

The description discloses the interaction method (Super, type, Enter) and instructs the agent to confirm with a screenshot, which adds behavioral context. However, it does not explain the meaning of the destructiveHint annotation – opening an app could potentially change focus or system state, but the description does not clarify the risk or why this is flagged as destructive. It adds some value but leaves a significant aspect unexplained.

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 extremely concise, consisting of two sentences with the purpose front-loaded. Every word contributes to explaining the operation and the confirmation step, with no fluff or redundancy. The structure is efficient and easy to parse.

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?

For a simple open/switch tool, the description covers the main operation and the confirmation step, but it lacks information about error handling (e.g., if the app is not found) and does not address the destructiveHint annotation. Given the tool's simplicity and complete schema, it is mostly adequate but could benefit from clarifying the destructive aspect to give the agent a fuller picture.

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 schema already provides a detailed description of the 'name' parameter (app name as it appears in GNOME's search), so the description adds no additional semantic information. With 100% schema description coverage, the baseline of 3 is appropriate – the description does not need to compensate for missing schema details.

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 action (open or switch) on a resource (an app) using a specific method (Activities search). It distinguishes itself from sibling tools like 'windows' or 'find' by focusing on launching an app, though it doesn't explicitly name alternatives. The verb and object are unambiguous, making the tool's purpose immediately understandable.

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 when to use the tool (when an app needs to be opened or switched to) but provides no explicit guidance on when not to use it or mention alternative tools. There are no exclusion criteria or conditions, so an agent might not know when to prefer this over other tools like 'windows' for listing open apps or 'find' for searching.

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