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

Annotations only declare readOnlyHint=true, so the description usefully adds that the tool returns credit cost, expected value, and per-tile rarity weighting. The dual mode (overview vs. single tile) is disclosed, which is behavioral context beyond the safety hint, though nothing is said about data freshness or how expected value is derived.

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 tightly written sentences: the first front-loads the dual behavior and the returned fields, the second states the use case. No filler or redundancy.

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 one-optional-parameter, read-only tool with no output schema, the description covers both invocation modes and what each returns, which is essentially all an agent needs. Minor gaps remain around pagination/rotation scope and data currency.

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 slug parameter's behavior (returns that tile with its full item list instead of the overview) is already spelled out in the schema. The description restates the same mode-switch, adding no format or validation detail beyond it, 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?

The description names a specific verb pair (list / get) and a precise resource (current Counter-Strike 2 Armory rotation tiles), and describes both operating modes distinctly. Neither of the siblings mentions Armory, so an agent can readily tell this apart from browse_cases or get_case_roi_ranking.

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 states the purpose clearly: 'Use this to compare what Armory credits are worth across the current rotation,' giving a concrete decision context. However, it never names an alternative or a condition under which a sibling (e.g., get_case_roi_ranking) would be the better choice.

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