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

The description discloses a non-obvious side effect—'Calls record usage and query metadata within POKEKA'—which goes beyond the bare readOnlyHint: false annotation. It also adds methodology transparency ('fixed-basket same-card index (never vibes)') and a disclaimer. No contradiction with the annotations exists.

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 first sentence is dense but packs a precise list of data elements, and the remaining sentences add necessary behavioral and disclaimer information. It could be more scannable as a bulleted list, but there is no filler or unnecessary repetition.

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 only one optional parameter, the description sufficiently covers the data scope, methodology, side effects, and disclaimers. The gaps are the omitted zh-cn track and lack of explicit sibling routing, which prevent it from being fully complete.

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 the baseline is 3, but the description's parenthetical 'all / en / ja' omits the valid 'zh-cn' value present in the enum. This makes the parameter documentation actively misleading rather than merely redundant, despite the schema being authoritative.

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 names the specific resource (a market brief) and enumerates its concrete contents: a one-line phase read, a fixed-basket same-card index, peak/drawdown numbers, weekly verified-sale counts, and a release/event calendar. This clearly separates it from siblings such as card_price, market_movers, or recent_sales.

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 the tool is for a market-cycle/phase overview, but it gives no explicit guidance on when to use it versus market_movers, market_volume_leaders, or recent_sales. It also lacks any when-not-to-use or alternative routing, leaving the agent to infer suitability from the listed contents.

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