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

Annotations already declare readOnly, idempotent, non-destructive and open-world, so safety is covered. The description adds genuinely useful behavior the annotations can't convey: the result set is capped at six featured items with exact-pack pricing and live availability, which tells the agent not to expect exhaustive results.

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?

Two sentences, zero filler, with the capability front-loaded and the scope caveat immediately after. Nothing repeats the annotations or the name.

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 single-param read tool with no output schema, the purpose and result shape are adequately covered. The unexplained 'query' parameter is the one real gap an agent needs closed before calling it.

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?

There is one optional 'query' parameter with 0% schema description coverage, and the description never mentions it. An agent cannot tell whether 'query' filters by name, style, or is ignored entirely — the description must compensate here and does not.

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 specific verb and resource ('Returns six featured IMPOSSIBREW beers') plus what data comes back (prices and availability). The scope limitation 'Not a full store catalogue' distinguishes it from a catalogue-style sibling like get_product, though it doesn't name which sibling to use for a full browse.

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?

'Not a full store catalogue' implies when not to use it, but no alternative tool is named for the full-catalogue case and no condition for using this one is given. Usage is implied rather than prescribed.

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