close_app

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

The description indicates the tool is destructive (corroborating the destructiveHint annotation) and does not end the session. It adds value by clarifying the session remains active, which is not in the annotation. However, it does not disclose other behaviors like whether the app can be reopened within the same session, what happens to elements, or if closing fails gracefully.

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 with two sentences, both of which are essential. It front-loads the action and constraint without any wasted words.

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 (no params, clear action), the description is mostly complete. However, it omits what happens after closing (e.g., can you relaunch?), any prerequisites (is the app already open?), or side effects (are stored references invalidated?). For a destructive action with no output schema, a bit more context would help the agent reason about consequences.

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 no parameters and schema coverage is 100%, so the description has little to add. The description does not need to explain parameters, making it sufficient. The score reflects that the description adds no new param info, but given the context, that is acceptable.

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 (close the application under test) and the constraint that it does not end the Appium session. It distinguishes from delete_session, which likely ends the session. However, 'under test' could be more precise (e.g., the current app or context), and without seeing delete_session's description, the distinction is implied but not explicit.

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 explicitly says 'Only call when explicitly asked,' which provides a usage guideline. This helps prevent accidental use. However, it does not explain when to use this tool vs. others like close_window or delete_session, leaving some ambiguity.

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