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

Annotations already indicate idempotent and non-destructive behavior; the description adds valuable context about the permanent vs session-only distinction, the exact token format (JWT), and that calling with no args returns a link. It does not describe the response when a token is provided, but given the simple scope, this is acceptable.

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 dense paragraph that front-loads the purpose and then explains the two usage modes. Though it could be better structured with bullet points, every sentence provides necessary information and there is no padding.

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 one optional parameter, no output schema, and strong annotations, the description covers purpose, usage modes, parameter semantics, and behavior. The main gap is the lack of detail on what the tool returns when a token is passed, but this is minor 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?

With 0% schema description coverage, the description fully compensates by explaining that the token parameter is an optional JWT and that omitting it returns a login link. It even specifies the exact call shape `{ token: '<jwt>' }`, which is more than the bare schema provides.

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 tool's purpose: authenticating to MCP.AI by logging in via browser and acquiring/using an access token. It provides specific actions ('log in in the browser, copy the access token') and distinguishes its role from siblings like 'connect' implicitly, though it doesn't explicitly name alternative tools.

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 gives concrete usage guidance for two scenarios: permanent connection via config header and session-only login via the token parameter or no-args link generation. It uses 'Best' and 'Or' to prioritize approaches, giving the agent clear context for when to use each call variant.

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