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

The annotations indicate idempotentHint=true and readOnlyHint=false, which means the tool may have side effects (e.g., initiating a login link). The description explains that calling with no args returns a link that requires a browser step, and calling with a token completes the login. It also mentions that the token is non-expiring if added to config. However, it does not disclose what happens on successful authentication in terms of session state or potential side effects beyond the link/token handling. Given the idempotent hint, the description does not contradict annotations but adds partial context about the two workflows. The bar is lower because annotations exist, but the description adds useful but incomplete behavioral context about session vs. permanent auth.

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 paragraph but covers all essential guidance: what to do in the browser, two alternative methods, and the parameter semantics. It is somewhat dense but not overly verbose. The structure is a bit run-on, but it front-loads the overall purpose and then explains the two options. Slightly more structure (such as bullet points) could improve readability, but as is, it is concise and earns its place.

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 tool's complexity (auth flow with multiple steps) and the lack of output schema, the description covers the essential steps: obtaining a token via browser, providing it either via config or via parameter. It doesn't describe the output of the tool (return value when successful or failure), but since there is no output schema, the description could benefit from noting that the tool returns a link or an authentication status. However, the description is sufficient for the primary use cases and is well-suited for an agent to understand the intended flow.

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 has only one parameter 'token' with no description, and schema_description_coverage is 0%. The description compensates by explaining that the token is a JWT to be pasted after the user copies it from the browser. It explains the login flow and when to provide the token vs. when to omit it. While it doesn't detail the token format (JWT is mentioned but not elaborated), it gives enough semantic meaning for an agent to use the parameter correctly. Given that the schema is almost empty, the description carries the full burden, and it does so effectively.

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 what the tool does: it authenticates the user for MCP.AI IDE agents by obtaining an access token, either via a browser login link or by accepting a pasted token. It also distinguishes between two ways of authenticating (permanent via config header, session-only via token parameter). This distinguishes it from sibling tools like 'connect' and 'marketplace' by focusing specifically on authentication.

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 guidance: log in in the browser, copy the access token; best practice is to add it to the server's config as a header for permanent connection; or paste the token into the tool call for session-only login. It explains when to use which mode, and implicitly contrasts with the config-based approach. While no explicit alternatives are named among siblings, the alternatives within this tool are clearly laid out.

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