indice_precos

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

With no annotations, the description carries the full burden and does disclose a meaningful behavioral trait: unauthenticated calls return only a 30-trading-day sample flagged with `aviso`, while `chave_api` unlocks the full history. It is silent on rate limits and anything beyond Keyth auth, but the tiered-response behavior is genuinely informative.

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?

Two tight sentences, front-loaded with what the tool returns and then the key-tier caveat. No 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?

No output schema or annotations exist, and while the return shape is described conceptually (daily points, oldest to newest, `aviso` field), the date-range and index-code parameters remain unexplained. Adequate for the happy path but not complete for a 4-parameter 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 0%, so the description must compensate. It clearly explains `chave_api` and implies temporal scoping, but never clarifies that `de`/`ate` are date bounds/format or what `codigo` selects (default IBOV), leaving two of four parameters effectively undocumented.

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 names a specific resource and granularity ("Fechamento DIÁRIO de um índice da B3, em pontos") plus the ordering of the series, so an agent knows exactly what is returned. It does not name any sibling (e.g. `indice`, `precos`) to disambiguate, so sibling differentiation is only implicit.

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?

It explains the access tier (sample vs. full series with a free key), which is useful context for deciding whether to call it, but gives no guidance on when to prefer this tool over `indice` or `precos`. Usage is implied rather than stated.

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