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

Annotations already indicate non-read-only, idempotent, non-destructive. Description adds context about auth flow (link generation, session vs permanent) and side effects (modifying config). No contradiction with annotations, and adds useful behavioral context.

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 but avoids fluff. It front-loads purpose and then details two usage modes with 'Best:' and 'Or', which is effective. Slightly long but earns its keep.

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 tool (one optional param, no output schema), the description covers invocation modes and outcome (link or session). It doesn't explicitly state return value but implies it. Complete enough for an agent to use correctly.

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 coverage is 0%, but the description explains the 'token' parameter's role (JWT for session login) and that omitting it generates a link. This compensates well, though it could explicitly state the parameter is optional.

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 authenticates to MCP.AI via browser login, token acquisition, and configuration. It distinguishes itself from siblings like 'connect' by specifying it's for authentication and providing a detailed workflow.

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 provides explicit when-to-use guidance: for permanent connection add header to config, or for session-only use token parameter or no args to get link. It doesn't explicitly name alternative tools but gives clear usage context, so not a 5.

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