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

Annotations already cover the safety profile (readOnlyHint, idempotentHint, openWorldHint=false), so the bar is lower. The description nonetheless adds real behavioral context: the link is consumed by a human in a browser, and the seed only receives tests, never sends, and takes no mailbox slot. No rate limits or link-expiry behavior is mentioned.

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 tight sentences: what the link is, what the seed does, and the operator-facing warning. The caution is front-loaded appropriately and every sentence carries information.

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 must describe what comes back, and it does — a consent-screen link for a human. It is nearly complete for a zero-param read tool, missing only practical details such as link reuse/expiry or what to do after the human completes consent.

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 tool takes zero parameters, so the schema leaves nothing to document and the baseline is 4. The description correctly focuses on output semantics rather than inventing parameter detail.

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?

States a concrete verb+resource: returns a browser link that connects a Gmail account as a seed inbox via Google's consent screen. The 'seed inbox' qualifier is specific. It does not, however, explicitly distinguish itself from the sibling get_mailbox_connect_link, so an agent must infer the difference between seed and regular mailbox linking.

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?

Gives clear context (a human opens this while signed in to AffiliateSpy to connect a seed inbox) plus an explicit when-not: 'Do not open it yourself.' It stops short of naming the alternative tool (get_mailbox_connect_link) for non-seed mailbox linking.

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