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

The description adds meaningful behavioral context beyond annotations: it distinguishes a permanent, non-expiring connection via config header from a session-only login via token paste. Annotations only indicate idempotent and non-destructive, and the description does not contradict them. It does not cover failure cases or side effects like token storage, but it discloses the key persistence 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 front-loaded with the essential login flow and is information-dense without excessive padding. It is somewhat run-on with multiple clauses, but each component earns its place: browser login, config header, token paste, and no-arg behavior.

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 simple one-parameter authentication tool with no output schema, the description is largely complete: it explains both invocation modes, the permanent vs session distinction, and how the login link is obtained. It does not mention errors, expiry details for pasted tokens, or what the tool returns beyond the implied link, but the core workflow is well covered.

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?

Schema description coverage is 0%, so the description carries the full burden and succeeds. It explains the optional 'token' parameter precisely as a JWT to paste, and clearly states that calling with no arguments returns the login link. This fully compensates for the bare schema.

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 an MCP.AI authentication/login flow: 'log in in the browser, copy the access token' and paste it or persist it via config. It avoids tautology and explains the core resource being authenticated. It does not explicitly contrast with sibling tools like 'connect', so it falls short of a 5.

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 concrete usage modes: call with no args to get the login link, or call with { token: '<jwt>' } for a session-only login. It also recommends the preferred permanent option ('Best: add it to this server's config'). However, it does not explicitly say when to choose this tool over its siblings, so it lacks full alternative guidance.

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