qso_stats

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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds a genuine behavioral caveat: the 'hour' axis depends on whether stored log times are JST or UTC, which the agent could not infer elsewhere. It does not describe the return shape, but no output schema exists and the axis list partially compensates.

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?

Front-loads the purpose in one short sentence, then a compact bulleted list of group_by meanings. Minimal waste, though the parenthetical about award_progress and the JST/UTC aside slightly interrupt the list flow.

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 an 11-parameter tool with no schema descriptions and no output schema, the description covers group_by well and delegates filters to search_qso, but never explains the top limit, default behavior, or output format. Adequate but not fully sufficient for correct invocation.

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 0% across 11 parameters, so the description must carry the load. It fully explains group_by values and delegates the filter parameters ('same as search_qso'), which is useful but indirect. Core parameters like top (result limit), date_from/date_to and qsl_rcvd receive no direct explanation, leaving real gaps.

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 and resource ('集計する' on 交信数) and enumerates the aggregation axes, so the agent knows exactly what the tool produces. It also differentiates from siblings by naming search_qso (shared filters) and award_progress (better for reading prefecture names).

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?

Clearly implies the aggregation use case and explicitly routes one scenario (prefecture names) to award_progress. However, it never states when NOT to use this versus search_qso, only that they share filter semantics, so the boundary is left partly implicit.

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