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

Since annotations are minimal (readOnlyHint=false, idempotentHint=true, destructiveHint=false), the description carries the burden. It clearly explains the behavior: it opens a login link, accepts a token for session login, and notes the permanent option via config. It also mentions that adding to config leads to a non-expiring connection, which is essential behavioral context. No contradictions with annotations are present.

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 front-loaded with the target audience and main action, then gives a step-by-step in two sentences. It is compact, informative, and every sentence adds value—no fluff.

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 a simple tool with one optional parameter and no output schema, the description is quite complete: it covers the login flow, token usage, and permanent config option. It could mention what happens on success/failure (e.g., response format), but that's not critical given the simplicity. Without an output schema, a brief note on return value would be helpful, but the description is adequate for an agent to use the tool correctly.

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 parameter 'token' with no description, and the description explicitly explains it: 'token: "<jwt>"' for session login. It adds meaning beyond the schema by specifying the format (JWT) and usage context. Since coverage is 0% but the param is fully explained, a 4 is appropriate; the only missing detail is explicit format (e.g., no regex or examples), but it's clear enough.

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: it authenticates IDE agents to MCP.AI by providing a login link and accepting an access token. It distinguishes from siblings by specifying the exact workflow (browser login, token paste, config header) and mentions alternatives like using the server config.

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 guidance on when and how to use it: 'call with { token: "<jwt>" } after the user pastes, or with no args to get the link.' It also provides a preferred alternative (adding to config) and explains the session-only vs. permanent distinction, which is clear usage context.

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