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

The description discloses the behavioral traits: it explains the session vs permanent relationship via config, and that calling without args returns a link. Annotations (idempotentHint=true, no destructive hints) are not contradicted. It adds context beyond annotations, such as the token format and the two login modes, though it doesn't mention potential side effects like invalidating prior sessions, which is a minor gap.

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 two sentences but the second is lengthy. It is front-loaded with the main purpose and then details usage. No wasted words; every phrase adds value. It could be slightly tighter, but the information density is high and well-organized.

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 this is a simple authentication tool with no output schema and minimal parameters, the description covers the essential context: both authentication methods, the token parameter semantics, and the permanent vs session distinction. It doesn't mention error handling or edge cases (e.g., expired tokens), but that is not critical for selecting and invoking the tool correctly. The sibling context and annotations complete the picture adequately.

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 input schema only defines 'token' as a string with no description, and schema coverage is 0%. However, the description explains the token parameter by showing usage 'call with { token: "<jwt>" }' and clarifies it is optional by stating 'or with no args'. This adds meaning beyond the schema, compensating for the lack of schema documentation. It could be more explicit about the token's format implications (JWT) but that is inferred.

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: 'log in in the browser, copy the access token' for MCP.AI with IDE agents. It explicitly names the resource (MCP.AI) and the action (authenticate). It also distinguishes itself from siblings like 'connect' by specifying this is for authenticating with MCP.AI, not general connection.

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 explains the two primary ways to authenticate (permanent via config header, or session-only by passing a token) and details how to call the tool ('call with { token: "<jwt>" }' or 'with no args to get the link'). It also indicates when to prefer the config approach ('Best: add it to this server's config') giving clear context.

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