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

The description goes beyond the annotations by stating that a no-argument call returns a link, that passing a token creates a session-only login, and that permanent access is better handled through a configured Authorization header. This is valuable context; only the detailed return shape after the session call is not described, but annotations already cover idempotency and non-destructiveness.

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 dense but stays focused; every sentence contributes either usage context or invocation instructions. It is not as terse as possible, but the extra guidance about permanent versus session-only login is valuable enough to justify the length.

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 simple parameter shape and absent output schema, the description covers the main expected usage modes and what the no-argument call returns. The only minor gap is not stating the exact response payload or success/failure behavior when passing a token, but this remains usable for practical agent invocation.

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 token parameter has zero schema description coverage, so the tool description must compensate. It does so reasonably by explaining that the token is a JWT, should be pasted from the browser, and is used for session-only login. It also clarifies that the parameter is optional since calling with no arguments gets the link.

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 identifies the tool as the authentication mechanism for the MCP server, specifying an actionable workflow: log in, obtain a token, and either configure it permanently or pass it for a session. It distinguishes itself from siblings by focusing specifically on authentication and login, not general connection or metadata operations.

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?

It explicitly explains when to use the tool: with no arguments to get a login link, and with a token for session-only login. It also directly contrasts this with the recommended permanent setup via server config, giving the agent a clear decision path between two authentication modes.

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