android_global_action

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

The annotations indicate destructiveHint=true and readOnlyHint=false, but the description does not elaborate on side effects (e.g., changing screen state, exiting apps). It only says 'perform a navigation action,' leaving behavioral details unexplained beyond the annotation flags.

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 a single, concise sentence with no redundant wording. It directly states the tool's purpose without fluff, achieving high efficiency.

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 and the enum schema, the description is minimally sufficient. However, it omits any mention of return values or side effects per action, and it assumes the agent knows what each navigation action does. A slightly richer description would improve completeness.

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 fully covers the parameter with an enum of possible actions (home, back, recents, notifications, quick_settings), so the baseline is 3. The description adds no extra meaning to the parameter values—it doesn't explain what each action does—but the enum is self-explanatory for a basic level.

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 a specific verb ('Perform') and resource ('native Android navigation action'), distinguishing it from UI interaction tools like android_ui_click and android_tap. It could be more specific by enumerating the actions, but the enum schema fills that gap.

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 usage for navigation actions but does not explicitly contrast with alternative tools. An agent can infer when to use this tool from the enum values (home, back, etc.), but no explicit guidance is given for choosing between this and other navigation-related tools.

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