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

Annotations already declare readOnlyHint/idempotentHint/destructiveHint=false, so safety is covered. The description adds genuinely new context: an auth requirement ('Precisa do token edm_…') and the shape of the result ('prazos e status de entrega'), which go beyond structured fields. It stops short of describing pagination or rate behavior, which the cursor param implies but the text never explains.

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, zero filler, with the resource and scope front-loaded before the token requirement. Every clause carries information.

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?

For a read-only list tool with full schema coverage and no output schema, the description covers what the tool returns at a high level and the auth prerequisite. Pagination behavior across the limite/antes_compra pair is left to the schema, a minor gap.

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%, with id, limite, and antes_compra all documented in the schema itself (including the pagination cursor semantics for antes_compra). The description adds no parameter-level detail, so the baseline 3 applies.

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 resource (purchases that already matched an alert) and scope (pull channel, with deadlines and delivery status), which reads as a list/query tool. It is distinguishable from create/edit siblings like criar_alerta and editar_alerta, though the verb is implicit and no sibling is named.

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 gives no explicit when-to-use or when-not guidance, nor does it point to alternatives such as meus_compras, compra, or vigiar_compra. The 'canal pull' parenthetical hints at the delivery model but leaves the selection condition to inference.

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