Get opening stats

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

With no annotations, the description carries full responsibility for behavioral disclosure. It mentions scanning recent games and aggregating by opening name, which adds some context. However, it implies that opening_name and color are required ('specific opening', 'given colour') while the schema marks them optional, creating ambiguity. It also does not disclose how 'recent' is determined or how missing/empty stats are handled.

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 very concise: two sentences, no fluff. The first sentence states the core function, and the second adds a brief note on how it works. All content is relevant and front-loaded.

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 has 5 parameters, no annotations, and a 0% schema coverage, the description is insufficient. It covers the basic purpose but leaves out important context about optional filters, interpretation of 'recent games', and potential edge cases. While the output schema exists and mitigates the need to describe return values, the description still omits guidance on how to use format and max_games.

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 0%, so the description must compensate. It partially explains the meaning of username, opening_name, and color, but completely omits format and max_games, which the schema leaves unexplained. The description's mention of 'specific opening' conflicts with the schema's optional opening_name, and it does not clarify the role of max_games or format filters.

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 states the tool's purpose: 'Win/draw/loss breakdown for one player in a specific opening, as a given colour.' It specifies a specific resource (opening stats) and a precise verb (breakdown), and it distinguishes from sibling tools like get_recent_games by focusing on aggregated results per opening.

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 explicit guidance on when to use this tool vs alternatives. The description only implies usage through its purpose, but does not mention any exclusions or sibling alternatives. For example, it does not clarify when to use get_opening_stats instead of get_recent_games or get_game_analysis.

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