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

Annotations provide idempotentHint=true and destructiveHint=false, which are helpful, but the description adds important context: it explains the two login modes, the token lifespan (permanent vs session-only), and how the token can be stored in config. It lacks explicit mention of side effects (e.g., modifying config), but the idempotent hint and the lack of destructive hint suggest safety. The description goes beyond the annotations by detailing the token handling.

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, front-loaded with the tool's identity and use case. Every clause adds value: the target audience, the login process, the permanent vs session distinction, and the invocation syntax. No waste; it reads like a compact guide.

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, token management, config vs session) and the lack of output schema and nested objects, the description is surprisingly complete. It covers all essential behaviors: how to authenticate, where to put the token, the two modes, and how to invoke the tool. It might not explain the response, but for an auth tool, the primary outcome (connection established) is implied. The description leaves little ambiguity.

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 has one optional optional string parameter 'token' with no description, so schema coverage is 0%. The description compensates well: it explains the token's purpose ('{ token: "<jwt>" }') and specifies that calling with no args returns the link. It also gives the context of the token (JWT) and where to obtain it (browser). The only gap is that it does not describe the response format, but with no output schema, that burden is on the description; it doesn't say what the function returns, but the purpose is clear.

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 verb ('authenticate'), resource ('MCP.AI for IDE agents'), and the mechanism (browser login, token copy, config header vs session token). It distinguishes from siblings by providing explicit login flow and alternatives, though it doesn't reference sibling names directly but the purpose is unmistakable.

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 gives explicit when-to-use and how-to-use: 'log in in the browser, copy the access token' and offers two modes (permanent via config header, session-only via token param). It also says 'call with { token: "<jwt>" } after the user pastes, or with no args to get the link.' This is far more than minimal guidance, though it does not explicitly say when not to use it, but for an authentication tool, the context is clear.

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