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

Annotations already declare idempotentHint=true and destructiveHint=false, so safety profile is known. The description adds that a permanent header connection is non-expiring and session-only is temporary, but doesn't describe return values, side effects (e.g., storing tokens), or failure modes. This is additional context but not rich behavioral disclosure.

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?

Three sentences covering purpose, permanent setup, and session login. Front-loaded with the main action, then branching usage. No redundant phrases; each sentence carries distinct information.

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 single-optional-param tool with no output schema, the description is fairly complete. It covers authentication flow, permanent vs session, and how to invoke with/without token. Missing error conditions or post-auth response details, but not critical for a simple auth tool.

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?

With 0% schema coverage, the description must compensate. It explains that 'token' is a JWT, is optional (no args allowed), and the two usage modes. However, it doesn't specify token validation, format details beyond JWT, or behavior when token is omitted or invalid. Some meaning added but incomplete.

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: authenticating an IDE agent to MCP.AI by logging in and obtaining an access token. It distinguishes from siblings like 'connect' and 'marketplace' by focusing on authentication flow and token handling.

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?

Provides explicit usage scenarios: recommended permanent header config, session-only token paste, and no-args to get login link. While it doesn't mention when to use alternative tools, it gives clear step-by-step invocation patterns, which is sufficient given the tool's unique role.

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