adb_current_app

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

No annotations are provided, so the description carries the full burden of behavioral disclosure. However, it says nothing about whether this is a read-only operation, what the output format looks like, or whether it requires an unlocked device or active display. For a query-style tool with zero annotation coverage, the description should at minimum disclose its read-only nature and output format.

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, efficient sentence with zero wasted words. It states the exact purpose without redundancy or filler.

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?

The tool has no annotations, no output schema, and a minimal description. For a query tool that returns app/activity info, it doesn't describe the output format (e.g., package name, activity name, format details), which is valuable context an agent needs to parse results. The description is too thin for the richness of the return value it would produce.

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 single parameter 'serial' has 100% schema description coverage ('device serial (host:port); omit if only one device'). The description adds no additional meaning beyond the schema. With 100% schema coverage, baseline 3 is appropriate since the schema already handles the parameter documentation.

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 'Report the foreground app/activity' uses a clear verb ('report') and a specific resource ('foreground app/activity'). It distinguishes this from siblings like adb_list_apps (list all apps) and adb_launch (launch an app), making it reasonably clear this queries the currently visible app. However, it could benefit from mentioning it does not modify anything.

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 context (when you want to know the foreground app), but provides no explicit when-to-use, when-not-to-use, or alternative tool guidance. Given the sibling set includes adb_launch and adb_list_apps, explicit differentiation would help, but the purpose is clear enough that an agent could infer appropriate usage.

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