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

With no annotations, the description carries the full burden of behavioral disclosure. It does reveal that the tool returns both increments and cumulative snapshots and warns against summing cumulative snapshots, which is a useful behavioral rule. It also mentions 'requested and actual coverage dates,' implying the tool may adjust or report date coverage. However, it does not disclose potential limitations, error cases, or whether the operation is read-only (though likely, no annotation confirms). The description provides some insight but is not exhaustive.

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 concise and efficient: two sentences that state the purpose, the return fields, and a critical data-handling instruction. It is front-loaded with the core purpose. It avoids unnecessary verbosity and every sentence earns its place. A brief mention of usage context would improve it, but for its length, it is well-structured.

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?

The description mentions the key return fields (coverage dates, download_increment_total, latest_download_snapshot), which is important because there is no output schema. It also gives a usage tip about summing. However, it lacks context on when to use this tool versus siblings, and does not explain what 'coverage dates' mean in practice or how the tool handles missing data. For a read-only data retrieval tool, it is reasonably complete, but given its complexity and the absence of annotations or output schema, more context would be beneficial.

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 parameters are already well documented. The description does not add meaningful new semantics for game_id, date_from, or date_to; it only references 'requested and actual coverage dates,' which loosely ties to the date parameters but adds no detail. The warning about summing is a result-handling note, not a parameter explanation. Since the schema already covers the parameters, a baseline of 3 is appropriate.

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 purpose: retrieving daily Google Play net download increments and cumulative snapshots for a game. It specifies the resource (game) and the data type (downloads), making it distinct from sibling tools focused on impressions, rankings, or delivery summaries. However, it does not explicitly name any sibling tools to differentiate, so it falls short of a top score.

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?

No guidance is provided on when to use this tool versus alternatives like get_game_trend, get_game_daily_impressions, or get_game_delivery_summary. The description only offers a data-aggregation tip ('Sum increments only; never sum cumulative snapshots'), which is about how to handle results, not tool selection. There is no mention of use cases, prerequisites, or exclusions.

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