Lichess MCP

Does 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 effectively describes key behaviors: it initiates an OAuth flow, opens a browser for user interaction, and is used for authentication purposes. However, it does not mention potential side effects like requiring user interaction, timeouts, or error handling.

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 highly concise and front-loaded, with two sentences that directly explain the tool's function and usage without any wasted words. Each sentence adds essential information about the OAuth flow and its purpose.

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 complexity (authentication flow with browser interaction) and lack of annotations or output schema, the description is mostly complete but could benefit from mentioning what happens after authorization (e.g., token storage) or error scenarios. It adequately covers the core purpose and mechanism.

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 tool has 0 parameters with 100% schema description coverage, so the baseline is 4. The description appropriately does not discuss parameters, as none exist, and instead focuses on the tool's action and purpose.

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 specific action ('Start the Lichess OAuth login flow') and resource ('Lichess chess account'), distinguishing it from sibling tools like 'lichess_auth_status' which checks authentication status rather than initiating it. The mention of 'Opens a browser for authorization' adds concrete implementation detail.

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 provides clear context for when to use this tool ('to connect, sign in, or authenticate your Lichess chess account'), but does not explicitly state when not to use it or name alternatives like 'lichess_auth_status' for checking existing authentication. The guidance is sufficient but lacks explicit exclusions.

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