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

The description discloses key behavioral traits: permanent non-expiring vs session-only login, and that no-arg calls return a link. Annotations already indicate readOnlyHint:false and idempotentHint:true, and the description is consistent with those. It adds context about the two authentication flows, though it could mention what happens on invalid tokens or the actual return value.

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 two sentences and densely packed with useful information, essentially no fluff. The main weakness is the awkward phrasing 'MCP.AI for IDE agents (Cursor, etc.): log in in the browser' which could be streamlined. Overall, it earns its place with high information density.

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?

The tool has one optional parameter and no output schema, so the description adequately covers the essential flows. It explains both authentication modes and the no-arg call, which is sufficient for typical usage. It might benefit from a brief note about response or error behavior, but this is not critical given 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?

Despite 0% schema description coverage, the description explains the token parameter is a JWT fetched after user login ('copy the access token', 'call with { token: "<jwt>" }') and clarifies the no-arg behavior. This compensates well for the minimal schema, though it could add details about token format validation or error cases.

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 indicates the tool's purpose is authentication for MCP.AI with instructions to 'log in in the browser, copy the access token.' Although the opening phrase is a bit convoluted, the verb+resource is clear and distinct from siblings like connect or marketplace. It could be more direct but is unambiguous.

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 explicit when-to-use guidance: permanent vs session login, including exactly when to call with a token ('call with { token: "<jwt>" } after the user pastes') and when to call with no args ('or with no args to get the link'). It even recommends the best practice with 'Best: add it to this server's config.' This exceeds baseline by giving actionable decision-making instructions.

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