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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so safety is covered. The description adds context about the data scope (history over 30/90 days) and that it covers the competitive map pool, but does not disclose any additional behavioral traits such as filtering restrictions, pagination, or response structure. That is acceptable given the read-only nature.

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 description is a single sentence that front-loads the key metrics and then scopes them to the map pool and timeframe. It is concise and avoids redundant detail. It loses a point for the slight inconsistency with the schema's timeframe list and the embedded map list could be considered an unnecessary elaboration, but overall it is efficient.

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 the read-only safety profile, the description does not need to explain return values or side effects. However, the mismatch in valid days values is a genuine gap that could cause incorrect parameter usage. The description otherwise gives a good overview of the data content, so it is adequate but not 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 would be 3, but the description actually introduces a contradiction: it says 'over the last 30 or 90 days' while the schema's days parameter explicitly allows 30, 90, 180, or 365. This misrepresents valid input and could mislead an agent. No extra meaning is added beyond what the schema already provides.

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 clearly identifies the data returned: team win rates, round win rates, CT/T splits across a defined map pool. This separates it from siblings like cs2_clutches or cs2_round_economy, though it does not explicitly name any alternative. The noun-phrase style is a minor drawback but the meaning is unambiguous.

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?

There is no guidance on when to use this tool versus alternatives. It does not mention when to prefer it over cs2_veto_sequence, cs2_round_economy, or player_stats, nor does it give exclusion criteria. The only implied use case is needing team-level map stats, which is thin.

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