Get Item

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

With no annotations provided, the description carries the burden of behavioral disclosure. It clarifies that the operation is a read (public catalog data) and that it uses the authenticated profile, which is useful for understanding side effects. However, it does not mention rate limits, error behavior, or whether the item might be inactive/deleted, which are minor gaps given the read-only nature is implied.

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 concise and front-loaded: the first sentence states the core purpose. It adds useful context about site_id and includes two usage examples, all in a compact format. No wasted words, every sentence contributes value.

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 tool's simplicity (single required parameter) and the presence of an output schema (which likely describes return format), the description provides sufficient context for an agent to call it correctly. It does not explain the output structure, but that is in the output schema, not the description's job. It covers essential usage nuances (site_id behavior) and examples, making it complete enough.

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 schema has 0% description coverage, meaning the description must compensate for explaining parameters. It explicitly explains the significance of site_id (selects profile, public data) and provides item_id format examples. The account parameter is not described in the description, but the schema has a detailed description for it, so the description's added value is mainly on site_id, which it handles well.

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 retrieves full details of a MercadoLibre listing by item ID, using a specific verb and resource. It distinguishes itself from siblings like search_items (which finds items) and update_item (which modifies), making its purpose unambiguous.

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 explains that any authenticated site profile can read any item, clarifying when site_id is relevant. It also provides usage examples that illustrate natural-language queries. However, it does not explicitly state when NOT to use this tool versus alternatives like search_items, though the purpose clarity helps fill that gap.

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