list_packages

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 correctly implies a read-only listing operation, mentions optional filtering, and indicates that the output provides package names usable by launch_app/stop_app. This is sufficient for an agent to infer safety and return structure, though it could explicitly state it does not modify the device.

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, well-structured sentence that front-loads the primary action and filter option, then immediately gives the use case. Every word earns its place, no redundancy.

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 low complexity (2 optional params, no output schema, no annotations), the description is nearly complete: it explains purpose, parameters briefly, and downstream usage. A minor gap is that it doesn't hint at the return format or that serial is for multi-device scenarios, but these are compensated by the schema descriptions.

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 description coverage is 100%, so the baseline is 3. The description adds no additional meaning to the filter or serial parameters beyond what the schema already provides; it just names the parameters in context. This is adequate but does not exceed the baseline.

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 lists installed package names, optionally filtered by substring, and explicitly communicates the use case: to confirm an app is installed and get its exact package name for launch_app/stop_app. This is a specific verb+resource combination that distinguishes it from siblings like get_app_details or install_app.

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 tells when to use this tool (to confirm an app is installed and get its exact name for launching/stopping), implying the subsequent action. It does not explicitly state when not to use it or mention alternatives among the many sibling tools, but the context is clear enough for an agent.

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