compras_pgc_por_catalogo

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

Annotations already declare this as read-only, idempotent, and open-world, so the bar for description-added behavior is lower. The description adds a useful 1-hour cache note and the endpoint, but the word 'todos' is potentially misleading given the pagination parameters (default page size 50); it does not disclose that retrieving the full set may require iterating pages.

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 short sentences, with the main action and endpoint front-loaded, followed by use cases and a cache note. It is efficient and free of filler, though the endpoint path could be considered slightly technical for general-purpose guidance.

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?

Given the output schema, annotations, and moderate complexity, the description is close to sufficient for tool selection and invocation. The main gap is the pagination nuance: the claim 'todos' is not harmonized with the page-size parameters, which an agent needs to know to obtain the complete result set.

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%, so the schema already documents all five parameters. The description reinforces the CATMAT/CATSER distinction and hints that quantities are part of the output, but it does not add substantial semantic detail beyond what the schema provides.

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 what the tool does: it lists all PGCs that include a given CATMAT/CATSER catalog item, and it names the exact open-data endpoint. The resource and filter are specific, making it distinguishable from generic 'list PGC' siblings, though it does not explicitly contrast itself with related PGC list/aggregate 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?

It provides concrete use cases ('Quais órgãos planejaram comprar esse item este ano? Em que quantidade?') and positions the tool as an input to ETP and quantitative benchmarking. It does not explicitly mention when not to use it or name alternative tools, but the stated context is clear enough.

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