compras_pncp_orgao_unidades

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

The description adds substantial behavior beyond the read-only/idempotent annotations: cache duration of 24h, coverage of state and municipal organs, and explicit 404 handling where it returns an informative `_erro_upstream` with alternatives instead of raising an exception. No contradiction with annotations exists.

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 front-loaded with the core purpose, followed by the endpoint, use case, coverage, cache, and error behavior. Every sentence earns its place, and the bold 404 section is a well-structured, useful addition without unnecessary repetition.

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 a single documented parameter, rich annotations, and an output schema present, the description covers what an agent needs: purpose, endpoint, intended use, cache semantics, coverage, and error behavior. Nothing critical is missing for calling this tool 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 coverage is 100% for the single `cnpj` parameter, and the schema already documents format, length, and an example. The description adds no new parameter-level semantics beyond the schema, so the baseline score of 3 is appropriate.

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 clearly states the tool 'Lista unidades administrativas de um órgão no PNCP' and identifies the exact PNCP endpoint. It also explains the practical purpose: discovering unit codes before filtering contracts. The verb-resource combination is specific and distinct from sibling tools.

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 provides clear context: it is useful before filtering an organ's contracting/contract data, and it notes broad coverage of states and municipalities. It does not explicitly list exclusions or alternative sibling tools for when not to use it, so it stops one short of full routing guidance.

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