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

The description discloses two operational modes (token vs. link) and the distinction between session-only and permanent authentication, adding context beyond the annotations (which already indicate idempotency and non-destructiveness). It doesn't contradict annotations, but could mention success/failure behavior.

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 somewhat verbose but well-organized, starting with the purpose, then presenting the preferred permanent method, then the session option and the no-args case. Each sentence adds value, though it could be slightly tightened.

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 description covers the main usage flows but does not specify the return value (e.g., the exact content of the link) or error handling (e.g., invalid token). Given the absence of an output schema, these details would improve completeness, but the tool is simple enough that this is a minor gap.

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 schema provides no description for the 'token' parameter (coverage 0%), but the description fully explains its meaning: it is a JWT for session login, and its absence triggers a link response. This compensates completely for the lack of schema documentation.

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 that this tool handles authentication by either providing a browser login link or accepting a token. It explicitly mentions 'log in' and 'token', distinguishing it from sibling tools like 'connect' or 'marketplace' which serve different purposes.

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 explicit usage instructions: call with no arguments to get a link, or with a token for session login. It also recommends a permanent configuration method (adding to config) as the best practice, effectively telling when to use this tool versus the alternative, and when not to (for permanent setup).

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