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

With no annotations, the description carries the full behavioral-disclosure burden. It adds useful context that results are limited to active ads and that billing costs 1 point per returned record, but it does not describe permissions, rate limits, pagination behavior, or error conditions.

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 two short sentences with no wasted words. It front-loads the tool's scope and follows with the important cost-per-record detail.

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 read/list tool with complete schema descriptions, the description covers the core scope and billing behavior. However, with no annotations and no output schema, it could say more about the returned listing shape or pagination expectations.

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 seller, max_items, and start_page. The description reinforces how the seller parameter accepts a user ID or profile URL, but it adds no meaning beyond the schema for the pagination parameters.

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 the resource as a seller's active Kleinanzeigen ads and the scoping input as user ID or profile URL. It is specific enough to distinguish seller-scoped listings from broader listing search tools, though it does not explicitly name or contrast with 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?

The description implies usage by naming the required input (user ID or profile URL), but it provides no explicit guidance on when to choose this tool over alternatives such as run_kleinanzeigen_sellers or run_kleinanzeigen_listings_search. No exclusions or prerequisites are stated.

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