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

Annotations already declare readOnlyHint=true, openWorldHint=true, and destructiveHint=false, so the safety profile is fully covered. The description adds useful context about the specific stats (FK, FD, conversion %) but does not disclose additional behavioral traits such as sorting, recency, or response shape; that burden is moderated by the existing annotations and output schema.

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?

A single, well-structured sentence that front-loads the resource and then lays out both usage modes with no filler. Every clause earns its place, and the description avoids restating the tool name or redundant schema details.

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?

Given the tool's simple two-optional-parameter interface, read-only annotations, and existing output schema, the description covers everything an agent needs to decide and call correctly. There is no missing operational context that would lead to misinvocation.

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 adds meaning beyond the schema by naming the returned metrics (First Kills, First Deaths, opening duel conversion %) and explicitly tying playerId to pro-player stats versus the global leaderboard. This helps the agent understand what each call mode will yield.

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 tool as providing first blood and opening duel statistics, with an explicit verb ('view') and resource (CS2 opening duels). It further distinguishes two distinct modes—player-specific stats versus global leaderboard—making its purpose unambiguous and separable from sibling CS2 tools.

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 clearly explains when to pass playerId versus omit it, giving the agent concrete conditional guidance. It does not explicitly name alternatives or exclusion criteria, but the context is clear enough for a read-only stats tool with a simple two-mode interface.

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