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

Annotations already declare readOnlyHint=true, openWorldHint=false and destructiveHint=false, so safety is covered. The description adds value beyond them: it states auth is required and that the tool returns offers 'at any status' along with their fills, which tells the agent the result may include terminal states and fill history. It does not discuss rate limits or edge cases such as an unknown id.

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?

Front-loaded with the use case, then the return behavior, then the auth requirement – each sentence contributes. Slightly dense with the quoted user phrasing ('did that offer get my tickets'), but nothing is wasted.

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?

With an output schema covering return values and annotations covering safety, the description supplies exactly the remaining gaps an agent needs: when to call it, how it differs from the list sibling, the status coverage, and the auth requirement. Nothing material is missing.

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% and the single parameter is fully documented in the schema (the standing_bid_id, sourced from list_my_open_offers). The description adds no further semantics about the parameter, 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 verb and resource ('get one specific open offer on the XP marketplace') and immediately frames the answerable questions (filled? how much left? did it get my tickets). It is clearly distinguishable from list_my_open_offers, which the description explicitly contrasts against.

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?

Opens with 'Use when the user asks about one specific open offer' and names the sibling it is not (list_my_open_offers), plus the condition that selects this tool over it: filled and rescinded offers that the list tool does not show. That is explicit when-to-use and when-to-use-the-alternative guidance.

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