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

Annotations already indicate idempotentHint=true and non-destructive. The description adds operational details: returns a login link when called with no args, accepts a JWT token for session login, and explains the permanent header approach. No contradiction with annotations, and the added context helps predict 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 a bit longer than strictly necessary but every sentence carries useful information: context, recommended setup, and invocation patterns. It front-loads the purpose and then details usage, making it scannable.

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 with one optional parameter and no output schema, the description covers both authentication flows and the config alternative. It doesn't explicitly state the return value when called with token, but the context makes it clear the tool facilitates login. Overall, no major gaps for the agent's decision-making.

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 has one optional string token with no description coverage. The description explains the token is a JWT pasted from the browser for session-only login, adding crucial meaning beyond the bare schema. This compensates for the 0% schema coverage.

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: authenticate to MCP.AI server by logging in via browser and capturing an access token. It distinguishes itself by specifying the target audience (IDE agents) and the two auth modes. Even without naming siblings, 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?

Explicit guidance is provided: recommends the permanent header-based config as best practice, explains session-only login via pasted token, and instructs when to call with no args vs with token. This gives clear when-to-use and alternative pathways.

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