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

Annotations already declare read-only, idempotent, non-destructive. The description adds behavioral detail: paginated response, returns ids + paging info, which goes beyond annotations. It also notes the endpoint, but no contradictions.

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 a single, information-dense sentence plus a final pointer. It front-loads the core purpose, then adds pagination, filter, and return details without redundancy. No wasted words.

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 4-param tool with no output schema, the description covers the core functionality, pagination, filter, and return type, and directs to a sibling for details. Missing only the 'account' parameter and any error/edge-case behavior, which are minor for a list tool.

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 0%, so description must explain parameters. It explains limit/offset via pagination and status filter with allowed values, but 'account' is never mentioned, leaving a parameter semantically unexplained. Partial compensation for schema gaps.

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 lists IDs of the connected seller's ads, specifies the underlying endpoint, and distinguishes it from mercadolivre_get_items (which provides details). This directly addresses what the tool does and separates it 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?

It provides a clear context: listing seller's item IDs, with pagination and status filtering. It explicitly directs to mercadolivre_get_items for details, offering an alternative. However, it doesn't contrast with search_items or other list tools, so guidance is not exhaustive.

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