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

Annotations already cover the safety profile (readOnly, idempotent, non-destructive, closed-world), yet the description adds real behavioral detail the agent could not infer: automatic downsampling to maxPoints with the most recent point always preserved, exclusion of points outside the window, and a note/dataStatus mechanism ('ok', 'sem-dados', 'defasado') for stale or missing data.

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?

Four tight sentences, front-loaded with the core purpose, then default window, then downsampling caveat, then data-quality fields. Every sentence carries an operational fact; nothing is redundant or padding.

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?

There is no output schema, yet the description explains the return structure (period/value points), the metadata fields (note, dataStatus with its three values) and the downsampling guarantee. For a 4-parameter read tool, an agent has everything needed to call and interpret it.

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 coverage is 100%, so the baseline would be 3, but the description adds semantics the schema does not: omitting from/to yields a 5-year default window, and maxPoints triggers lossy downsampling that keeps the newest point. The interaction between from and the source's actual start date is also explained.

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 — 'Devolve a série temporal de um indicador' — plus the shape of the returned points (period/value). It is clearly distinct from get_indicator_latest or compare_indicators by implication, but never names a sibling to make the distinction explicit.

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 default behavior ('Sem from/to, traz os últimos 5 anos') implies when the tool is appropriate, but there is no explicit statement of when to prefer it over get_indicator_latest (single value) or compare_indicators (multi-series). Usage is inferable rather than stated.

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