List App Store apps

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

The description adds behavioral context beyond the annotations: it notes that the tool shows install state and renders no UI. This is consistent with readOnlyHint=true and provides useful additional insight into what the agent should expect from the tool's output and side effects.

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 two sentences, with the primary purpose front-loaded in the first phrase. Every word contributes to meaning, and there is no 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?

For a zero-parameter read-only listing tool with an output schema and clear annotations, the description provides everything needed: what the tool lists, the install-state information, the no-UI behavior, and a pointer to the alternative for UI. No gaps remain.

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 tool has zero parameters, so the description doesn't need to clarify parameter meanings. It adds value by describing the content of the list (ready-made, high-quality apps shipped with the engine) which helps the agent understand what the tool returns. Baseline for zero params is 4, and the description meets it.

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's function with a specific verb ('browse') and resource ('built-in App Store'), and distinguishes itself from sibling open_app by explicitly noting that it renders no UI. This makes its purpose unambiguous and differentiated.

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 explicitly tells the agent when to use this tool: to browse the built-in App Store programmatically. It also provides an explicit alternative, open_app {app: "app-store"}, for when a UI is desired, making the usage boundaries clear.

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