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

Annotations already cover read-only, idempotent, and non-destructive behavior. The description adds a useful behavioral nuance: 'Metric names differ per store because each store reports its own set.' This goes beyond the schema and helps set expectations. No contradiction with the 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 compact and front-loaded, with two sentences that earn their place. However, the phrase 'aggregate days' is slightly awkward and potentially redundant alongside 'the most recent daily rows', which keeps it from being perfect.

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 rich annotations and the presence of an output schema, the description supplies sufficient actionable context for a safe read-only call. It also adds the store-specific metric caveat. Explicit sibling differentiation would make it fully complete.

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 loosely reinforces the 'date window' concept and the one-app/one-store scope, but it does not add meaning beyond the schema's parameter descriptions.

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 uses a specific action and resource: it 'Summarize downloads, installs, uninstalls, crashes and other engagement totals' for one Appskyline app over a date window. It also describes the typical output: aggregate values, recent daily rows, and top territories. It does not explicitly name sibling alternatives, so it stops short of a 5.

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 gives clear context: one app, one store, a date window, and store-reported engagement metrics. It does not explicitly list when not to use this tool or point to alternatives, but the scenario is clearly scoped.

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