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

With no annotations, the description carries the full burden. It usefully discloses that the response includes the number of readings and days of tracking, and explicitly warns when tracking is too sparse to support a drop claim. However, it does not cover permissions, rate limits, or broader response structure.

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 three efficient sentences, front-loading the core purpose and then the output caveat. No sentence is wasted, though it could be slightly tighter.

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 simple two-parameter read tool with no output schema, the description gives enough input flexibility and output caveat for an agent to invoke it correctly. It lacks explicit sibling routing, but the core operational picture is complete.

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 both parameters. The description reinforces that produto accepts either a numeric ID or a full product URL, but adds no detail about the idioma parameter 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 identifies a specific resource and capability: an observed price series for an AliExpress product. It is understandable without opening the schema, though it does not explicitly differentiate itself from siblings like quedas_de_preco or buscar_promocoes.

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 accepted inputs (itemId or product URL) and implies relevance to drop-claim validation, but does not state when to use this tool versus the sibling tools. Usage is inferable but not explicitly directed.

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