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

The description adds context beyond the annotations (which already indicate idempotency and non-destructiveness). It explains that it can return a login link or accept a token, and clarifies that the token is a JWT. It also notes the permanent vs session distinction. This adds useful behavioral detail without contradicting the 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 a single long sentence that is somewhat rambling Commentary, but it is not overly verbose. It could be more structured (e.g., separate the two modes), but it conveys the needed information without redundancy. It is acceptable but not exemplary.

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 an authentication tool with a single optional parameter and no output schema, the description covers the main aspects: how to initiate login, how to provide a token, and the difference between permanent and session-scoped access. It lacks explicit details about response format, but that is not critical for this tool's purpose. It is sufficiently complete given the context signals.

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 has 0% description coverage, so the description must fill the gap. It does: it explains the `token` parameter's purpose (a JWT to paste for session-only login) and indicates it is optional (call with or without it). The description gives sufficient context for the parameter's usage.

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: it handles authentication by either providing a login link or accepting a token. It uses action verbs like 'log in' and 'paste', and references the resource (access token). It doesn't explicitly distinguish from sibling tools like 'connect', but the action is clear.

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 two explicit usage modes: with a token for session login, or without args to get a link. It also mentions the alternative of permanent configuration via header, giving context on when to use each. It does not explicitly state when not to use it, but the guidance is clear.

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