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

Annotations already declare readOnlyHint=true and openWorldHint=true, so safety and scope-of-world are covered. The description adds a meaningful behavioral detail beyond the annotations: results are aggregated across every source auction house the search carries, which tells the agent the corpus is cross-source rather than Alt-only.

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?

Two tight sentences with zero filler; the corpus definition is front-loaded and the filtering tip follows. Nothing repeats the tool name or wastes the agent's attention.

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 present and annotations covering safety, the description need not explain return values, and the aggregation scope is a useful addition. It is nearly complete; the only gap is routing guidance among the many alt_* sibling tools.

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 100%, so all six parameters are already documented in the schema, and the description's only parameter hint (auction_house=Alt) merely restates the schema text. Baseline 3 is appropriate when the schema does the heavy lifting and the description adds no new parameter meaning.

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 (Search) and resource (Alt's global archive of completed card sales), which is more precise than a generic search. It distinguishes itself from live-listing siblings by emphasizing 'completed' sales, but it never names an alternative such as alt_card_search or alt_auctions, so the differentiation is implied rather than explicit.

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 gives one concrete usage tip — pass auction_house=Alt to restrict to Alt's own auctions — which is genuine guidance. However, it offers no when-to-use vs when-not-to-use context relative to the other alt_* search tools, leaving the agent to infer selection.

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