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

Annotations already declare readOnlyHint=false, destructiveHint=false, and idempotentHint=true. The description adds useful context beyond these: it explains the two authentication flows (permanent config vs. session token) and that calling with no args returns a login link. No contradiction with annotations, and the additional context on how the token is used enhances transparency.

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 slightly verbose but every sentence adds value. It front-loads the purpose and then details the two usage modes concisely. The structure is logical, starting with the permanent setup recommendation and then the session-only alternative.

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 one optional parameter and no output schema, the description covers the essential aspects: how to authenticate permanently, how to do session-only, and what the parameter is. It is complete enough for an agent to invoke the tool correctly, though it doesn't describe the response format (e.g., success/failure) which could be useful.

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 only defines 'token' as a string, but the description provides meaning by specifying it should be a JWT and explains how it is used in both modes (as a header for permanent config or as the { token } argument for session login). With 0% schema coverage, the description compensates well for the parameter's semantics.

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 to MCP.AI for IDE agents by logging in and obtaining an access token. It uses specific verbs ('log in', 'copy the access token') and describes the resource (server config or session token). While it doesn't explicitly differentiate from sibling 'connect', the purpose is unambiguous.

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 explicit usage instructions: it recommends adding the token to the server config for permanent access, and offers two calling modes (with or without a token) for session-only login. It gives clear context on when to use each approach, though it doesn't explicitly mention when not to use this tool vs. alternatives.

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