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

Goes well beyond the annotations: discloses that data is preserved, that the app remains launchable, which app kinds are supported (Store apps and create_app apps), that it survives update_app, the specific failure mode ('not_installed'), and that the action is recorded in device_log. This is exactly the reversibility and side-effect context an agent needs for a mutating but non-destructive toggle.

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 core action and its inverse are front-loaded in the first clause, followed by short factual sentences covering retention, compatibility, failure, and logging. No sentence is padding; each carries a distinct fact.

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 3-parameter mutation with no output schema, the description covers reversibility, data retention, supported app types, sibling interoperability, the error case, and audit logging. Nothing an agent needs in order to call this correctly is missing.

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 100%, with each of session, id, and hidden already documented in the schema. The description reinforces the meaning of hidden: false as 'show' but adds no format, constraint, or edge-case detail beyond the schema. Baseline 3 applies.

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?

States a specific verb and resource ('hide an installed app from the home screen and the app list') and immediately covers the inverse operation via 'hidden: false'. This clearly separates it from adjacent siblings like uninstall_app or kill_app, since the app is not removed or stopped.

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?

Explicitly frames the hide/show dichotomy and makes the key distinction from removal by saying the app keeps its data and still opens with switch_app and run_app_action. It does not name an alternative tool to use instead when true removal is wanted, but the contrast is strong enough for correct selection.

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