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

The description discloses the behavior of generating a login link with no arguments, as well as the distinction between permanent (config header) and session-only (pasted token) connections. It adds context beyond the annotations (idempotentHint=true) by explaining the non-expiring nature of the config approach, without contradicting any annotations.

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 functional but somewhat stream-of-consciousness, combining context, a recommendation, and usage instructions into a single run-on paragraph. It could be better structured with bullet points or separate sentences for clarity, though every sentence adds value.

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 simplicity (one optional parameter, no output schema), the description covers the essential flows: config-based and session-based, including the outcome of each. It omits error handling or success responses, but for an auth tool this is sufficient.

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?

Although the schema only defines 'token' as a string, the description clearly explains its expected format (JWT) and usage via the example `{ token: '<jwt>' }` and the no-arg case. It fully compensates for the lack of schema-level descriptions, providing complete semantic meaning.

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 explicitly states 'MCP.AI for IDE agents (Cursor, etc.): log in in the browser, copy the access token,' making the tool's purpose unmistakable. It uses a specific verb ('authenticate') and resource ('MCP.AI'), and is clearly distinct from sibling tools like 'connect' or 'marketplace' by focusing on authentication.

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 offers explicit usage guidance by contrasting 'Best: add it to this server's config as a header' for a permanent connection versus 'paste it here for a session-only login.' This effectively tells users when to choose each flow, though it does not explicitly mention alternative tools or when not to use them.

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