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

The annotations already disclose mutating, non-destructive, non-idempotent behavior. The description adds valuable traits beyond the annotations: private, single-use, valid for 15 minutes, works once, and requires no password or email code. These are exactly the behavioral details an agent needs before offering the link.

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 three tight sentences and front-loads the core action. Every sentence adds useful information: what the link is, how long it lasts, how to hand it off, and that it is free to call.

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?

An output schema exists, so return values need not be explained. With annotations covering safety behavior and the description covering creation, validity, handoff, authentication bypass, and cost, the definition is complete enough for an agent to invoke it 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?

Schema description coverage is 100%, so the schema already documents both plan and action in detail. The description mirrors some action semantics (checkout for upgrade/renew, account page for cancel/email/new connection address) but adds only marginal parameter-specific meaning beyond the schema.

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 gives a specific verb and resource: "Create a private, single-use link" that routes the user to checkout or account pages. It is clear what the tool does, though it does not explicitly name sibling alternatives such as buy_plan or get_my_account, so sibling differentiation is implied rather than stated.

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?

It gives clear usage context: "Give it to the user to click; no password or email code needed" and "Free to call." However, it does not explicitly say when to prefer this over sibling tools like buy_plan or get_my_account, nor does it state exclusions.

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