get_app_usage

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

With no annotations provided, the description carries the full burden of behavioral disclosure. It does not mention side effects, required permissions, read-only nature, return format, or any operational quirks. The description simply states what is retrieved, offering minimal insight beyond that.

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 sentence, front-loaded with the core action. It is readable and efficient, though the phrase 'screen time statistics' is somewhat redundant with 'app usage' and the omission of procstats is a minor structural gap.

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?

Despite schema coverage, the tool has no output schema, so the description should explain the return format or behavior. It does not, leaving the agent uncertain about the output. Additionally, the service parameter supports procstats but the description only mentions two of three services, making the tool's coverage incomplete.

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 description coverage is 100%, so the parameters are already well documented. The description adds slight context by naming the services but does not explain serial or packageName beyond what the schema provides. It also omits procstats from the service list, failing to fully complement the schema.

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 tool retrieves app usage and screen time statistics, using a specific verb and resource. It distinguishes from siblings like get_cpu_usage and get_app_memory. However, it only mentions usagestats and batterystats, omitting the procstats option available in the schema, causing slight incompleteness.

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 provides no explicit guidance on when to use this tool versus alternatives like get_app_memory or get_cpu_usage. It does not mention any exclusions or preferred scenarios. The only implied usage is that it retrieves app usage statistics, which is insufficient for effective tool selection.

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