Retrieve a Chess.com player's statistics by username, including ratings, win/loss records, and more.
Get the statistics of a chess.com player by username.
:param username: player username.
:return: player statistics information.
| Name | Required | Description | Default |
|---|---|---|---|
| username | Yes |
| Name | Required | Description | Default |
|---|---|---|---|
| result | Yes |
Changes observed during successful MCP inspections.
v0.1.0Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?
With no annotations provided, the description carries the full burden of behavioral disclosure. It indicates a read-only retrieval but does not mention any authentication requirements, rate limits, or error behaviors. The return value is vaguely described as 'player statistics information' without specifics, offering minimal transparency beyond the obvious.
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 brief and front-loaded with the primary action. However, the docstring format adds redundant lines (':param' and ':return') that could be omitted without losing clarity. It is still concise and efficient, though not perfectly lean.
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 tool with an output schema, the return format need not be detailed, but the description offers only a vague 'player statistics information.' With no annotations and no usage guidance, an agent lacks context on error handling, edge cases (e.g., invalid usernames), or any prerequisites. This is insufficient for a complete picture, even for a simple get operation.
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 has 0% description coverage for parameters, so the description must compensate. It includes a docstring line ':param username: player username' which merely repeats the property name and adds no additional meaning about format, constraints, or usage. This does not meaningfully aid the agent beyond what the schema already conveys.
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 action ('Get the statistics') and resource ('chess.com player by username'), which distinguishes it from the sibling tool get_chess_player_profile by focusing on statistics rather than profile. It is specific but does not explicitly name the sibling, so it falls short of a perfect 5.
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 the sibling get_chess_player_profile. The description only states what it does, not the conditions for choosing it over alternatives. This leaves the agent to infer usage from the tool name.
Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.