listar_modalidades

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

No annotations are provided, so the description carries the disclosure burden. It makes clear this is a static reference table (a read-only lookup), but says nothing about auth requirements, caching, or that the set of codes is fixed. Adequate for a zero-parameter lookup but not rich.

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 short sentences, both front-loaded with the essential fact (what it is) followed by the action rule (when to call it). 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?

With an output schema present, the return shape needn't be described, and the zero-param schema needs no parameter explanation. The description supplies purpose plus timing, leaving only minor behavioral details unstated.

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?

The tool takes zero parameters, so the baseline is 4. Nothing in the description misrepresents how it is called.

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 precise resource — the PNCP procurement-modality code table — and implicitly the verb (listing/consulting it). An agent can immediately tell this is a reference lookup distinct from the action-oriented siblings like buscar_editais or detalhar_contratacao.

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 gives an explicit when-to-use rule: consult this before passing the 'modalidade' value to the other tools. That directly routes the agent's sequencing behavior, which is unusual and valuable for a lookup tool.

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