Статистика

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

Annotations already declare readOnlyHint=true and openWorldHint=true, so the safe-read nature is covered structurally. The description adds useful context beyond that: money is returned in rubles, output is TSV, and the backing service is ReportService. It does not disclose limits on campaign count, date-range constraints, or any rate limits.

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?

A single dense sentence with the resource and metric list front-loaded and no filler. The trailing '(ReportService, TSV)' parenthetical is compact and informative, though slightly implementation-flavored for a description.

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?

With no output schema, the description does double duty and partially covers it by listing the metric columns and the TSV format. However, it omits how many campaigns can be queried at once, any date-range limits, and whether results are aggregated or per-day, leaving gaps for a reporting 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?

Schema description coverage is 100% (all four parameters documented, including default fields and the ruble note), so the schema carries the parameter burden. The description's 'расход (руб)' only echoes what the schema already states about currency. 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?

States a specific verb+resource ('Статистика кампаний за период') and enumerates the metrics returned (показы, клики, расход, CTR, CPC). It is clearly distinguishable from sibling tools like get_campaign or list_campaigns, which manage entities rather than report metrics. No explicit sibling differentiation is needed here since none of the siblings are statistics tools.

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?

There is no statement of when to use this tool versus alternatives, no prerequisites (e.g. campaign must exist), and no exclusions. The period and campaign scope are implied only by the required parameters, not by the description text.

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