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

The description adds behavioral context beyond the annotations by explaining that it only reads and changes nothing, and by indicating it returns both KPI aggregates and variation versus the previous period. Since annotations already cover readOnlyHint and idempotentHint, the description's extra value is moderate but meaningful; no contradiction is present.

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: it states the returned data first, then the read-only guarantee, then the routing to alternatives. Every sentence earns its place, and there is no redundant or vague filler.

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 a read-only summary tool with one optional parameter and no output schema, the description is complete: it defines what is returned, the period concept, the safety profile, and how to choose related tools. An agent has enough information to select and invoke it correctly.

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% for the single parameter, and the parameter has an enum with a clear description of each period option. The description refers to 'periodo' but does not add details beyond the schema, which is acceptable because the schema already carries the burden fully.

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 verb ('Devuelve') and names the exact resource: aggregated KPIs for a period, listing the metrics (energía, facturado, margen neto, sesiones, clientes) and the variation versus the previous period. It clearly distinguishes itself from sibling tools by naming what it is not, such as session-level detail and real-time status.

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 explicitly states when to use this tool versus alternatives: use askacharge_listar_sesiones for session-by-session detail and askacharge_estado_en_vivo for current activity. It also signals this tool is read-only, reinforcing it as a safe periodic-summary choice.

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