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

Annotations already declare readOnlyHint=true, idempotentHint=true, and destructiveHint=false, so the description does not need to restate those. It adds valuable context about the return fields and the prerequisite role of this tool, enhancing the agent's understanding beyond the structured annotations.

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 concise sentences plus an example question. The first sentence delivers the core function, the second provides a clear usage directive, and the example clarifies the intent. No redundancy or unnecessary detail.

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 0-parameter list tool with an output schema, the description fully covers what the tool returns and when to use it. The presence of an output schema means return-value details are already documented, so the description is complete for the agent to select and invoke the tool correctly.

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?

This tool has zero parameters, making schema coverage trivially 100%. The description does not need to explain parameters, but it does highlight the appStoreId as the key linking value for other tools, adding conceptual meaning to the tool's role in the workflow.

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 returns every tracked app with specific fields (store id, store, platforms, categories, ownership status). This distinguishes it from sibling tools like get_app_history or get_chart_top that operate on specific apps. The verb 'Returns' is precise and action-oriented.

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 instructs to 'Call this first' and explains that other tools identify apps by the appStoreId returned here, providing clear when-to-use guidance. However, it does not explicitly mention when not to use it or name alternative tools, so it falls slightly short of a perfect score.

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