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

Annotations already declare readOnly, idempotent, non-destructive and closed-world, so the safety profile is covered. The description adds genuinely non-redundant behavior: the required auth scope and the critical clarification that this tool never performs the share, which prevents an agent from over-promising an action.

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 hard requirement and followed by the key behavioral caveat and the return value. Nothing is repeated and no sentence is 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?

For a one-parameter read tool with no output schema, the description covers the auth prerequisite, the non-obvious limitation, and the nature of the returned link. It stops short of saying whether the link expires or is bound to a session, a minor gap given the tool's simplicity.

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 optional 'lender' parameter is already documented in the schema as the lender to mention in the hand-off. The description adds no further syntax, format, or defaulting details beyond that, so the baseline of 3 applies.

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 uses a specific verb-and-resource framing ('Returns the link where the shopper reviews and shares it themselves') that tells an agent exactly what comes back. It also carves out a boundary ('Does NOT share anything'), which separates it from any implicit 'share' behavior an agent might assume, though it never names a sibling tool.

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?

Preconditions are stated explicitly: the shopper's Safe Rate sign-in with the poppy:read scope, plus the note that actual sharing always requires the shopper's own click on saferate.com. That's clear when-and-how context, but no explicit alternative tool or exclusion path is offered.

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