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

With no annotations, the description carries the full behavioral disclosure burden, and it does so meaningfully. It clarifies that download_increment sums daily increments over actual coverage rather than cumulative downloads or public store ranges, and it discloses the inclusion of a legacy nested summary. That goes well beyond a surface-level description, though it does not mention auth, rate limits, or error conditions.

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 tight sentences that front-load the primary purpose, add one essential definition, and then disclose the legacy summary inclusion. Every clause carries information, and there is no padding or repetition of schema content.

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 that there is no output schema and no annotations, the description does a good job of explaining what the summary covers and one important measurement nuance. It also flags the legacy nested summary structure. It doesn't dwell on return format details, but the field-level descriptions are enough for a simple summarizing tool.

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 input schema already fully documents game_id, date_from, and date_to (100% coverage), including defaults and range limits. The description reinforces the 'within a date range' context but does not add new parameter-level meaning beyond the schema. The download_increment nuance is about output fields rather than parameters, so a baseline 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 states a specific verb ('Summarize') and a clear resource ('creatives, ad plans, lifetime exposure references and Google Play net download increments') framed by a date range. It is clearly distinct as a summary endpoint, but it does not explicitly name or contrast with sibling tools like get_game_overview, so it earns 4 rather than 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 implies when to use the tool – when you need a summary of these specific fields within a date range – but it never explicitly states exclusions or compares with alternatives. There is no explicit when-not-to-use guidance, so it sits at the 'implied usage' level.

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