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

The annotations already declare a read-only, open-world operation, so the safety profile is covered. The description adds useful disclosure about what is returned (source previous/new bounds, observation times, nextCursor) and that nothing is synthesized, but it says nothing about rate limits, result caps, or ordering of the update stream.

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?

Three tight sentences with the core action and output front-loaded, then the parameter rules, then the scope exclusion. The phrase "as before" is slightly vague, but no sentence is filler.

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?

An output schema exists, so return-value documentation is largely redundant but harmless. Pagination via nextCursor, platform selection, and the extinct filter are all covered; only error handling and result limits are unaddressed for what is a simple read-only 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 100%, so the schema already documents all three optional parameters; the description earns credit only for framing them as a coherent workflow. It reinforces cursor reuse for paging and the extinct/platform defaults, but does not add syntax or format detail beyond the schema.

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 opens with a specific verb and resource: "List native FC27 price-range updates." That is meaningfully narrower than the sibling price tools (futgg_fc27_prices, futgg_fc27_price_index), though it never names an alternative to make the distinction 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?

It gives concrete selection rules: choose platform ps5 or pc, set extinct to yes only if you want items extinct before the update, and reuse nextCursor unchanged for older records. It also scopes out related concerns ("No price history, ranking or account state"), which implicitly routes those requests elsewhere, but no sibling is named.

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