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 real value beyond that: it is "static," involves "no lookup," and is deterministic ("always the same answer for a given language"), reinforcing the idempotent hint with concrete behavior.

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?

It is a single front-loaded sentence led by the resource, with the determinism caveat closing it out. Dense but every clause maps to a distinct piece of returned content, with little waste.

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 carries the burden of describing returns and does so thoroughly: codes, usage instructions, links, support, and exact compliance wording. Combined with rich annotations and a single optional parameter, nothing an agent needs to call it correctly is missing.

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 language enum and English default are already documented in the schema. The description only gestures at language via "for a given language"/RxGRP and adds no syntax beyond the schema, so baseline 3 is appropriate.

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 names a specific resource and enumerates its contents (RxBIN/RxPCN/RxGRP codes, pharmacy-counter instructions, wallet-pass/card-page links, member support, compliance wording), so an agent knows exactly what it gets back. It also marks this as a static card distinct from lookups, separating it from find_drug and get_prices.

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?

"No lookup involved — always the same answer for a given language" tells the agent this is a deterministic static fetch needing no user-specific input, which is clear usage context. It stops short of explicit when-to-use/when-not routing, but the sibling tools (find_drug, get_prices) are functionally distinct, so alternatives are not really in play.

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