get_player_matches

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

No annotations are provided, so the description carries the full behavioral burden. It adds useful context by specifying the match statuses (registered, active, finished), but it does not disclose rate limits, authentication needs, error behavior, or whether the list is paginated. For a simple read-only list tool, the status detail is helpful but not comprehensive.

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, front-loaded sentence that wastes no words. It directly states the action and the object. Every element earns its place.

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 single-parameter list tool with no output schema, the description adequately covers the core purpose and scope. It doesn't explain return value structure or ordering, but that is often unnecessary for a simple list endpoint. Slight gap remains due to lack of any fallback/error behavior mention, but it's complete enough for the tool's simplicity.

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?

The schema description coverage is 100% (the username parameter is described as 'Chess.com username'). The tool description adds no additional meaning beyond what the schema already provides. Baseline of 3 is appropriate per the rubric.

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 outcome: 'List a Chess.com player's registered, active, and finished team matches.' The verb 'List' plus the resource (player's team matches) is specific and distinguishes it from sibling tools like get_team_match (which likely fetches a single match) and get_player_games (which likely covers all games).

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 implies the usage context: use whenever you need a player's team match list, including various statuses. It doesn't explicitly exclude alternatives, but the phrasing and sibling names make the appropriate scenario clear. Lack of explicit 'use instead of X' keeps it from a 5.

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