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

Annotations already declare readOnlyHint, idempotentHint and non-destructive, and the description adds meaningful context beyond them: nothing is actually connected until the owner completes the browser grant, so the agent knows this call has no side effect on its own. Missing details like link expiry or reuse behavior keep it from a 5.

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?

Three short sentences, front-loaded with the return value, then the human prerequisite, then the follow-up call. No filler.

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?

With no output schema, the description does state what is returned (the secure link) and the human-in-the-loop requirement that governs when the connection becomes real. It stops short of describing the link's shape or lifetime, a minor gap for a one-parameter read tool.

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 coverage is 100% and the single enum parameter is fully documented in the schema, so the baseline is 3. The description's mention of Google Calendar/Outlook mirrors the enum but adds no format or constraint detail beyond it.

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?

Specific verb and resource: returns a secure link for connecting Google Calendar or Outlook. It is clearly distinguishable from siblings like calendar_list or onboarding_get_status, which read state rather than produce a connection URL.

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?

Explains the flow: the owner must open the link in a signed-in browser and grant access, and instructs to call onboarding_get_status again afterward. It gives clear context and next step, though it does not name an explicit alternative for providers outside GOOGLE/OUTLOOK (that is only in the schema).

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