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

Annotations already declare readOnlyHint and idempotentHint, so safety is covered. The description's added detail (EUR pricing, deliverables, checkout URLs) largely restates what the output schema supplies, and the claim that packs 'unlock premium evidence generation directly in MCP' is promotional rather than operational. It adds little behavioral context beyond structured fields.

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?

Front-loaded with the core purpose in the first clause, and the three sentences are short and ordered (what it lists, what it returns, what packs unlock). The closing upsell sentence is the only expendable part, keeping it just short of a 5.

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 an output schema carrying return values, annotations covering safety, and a single optional enum parameter, the description supplies everything an agent needs: object of the listing, purchase channel, and payload contents. No material gap remains for a simple read-only catalog tool.

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% and the single 'category' parameter has its enum values fully documented in the schema. The description does not mention the filter at all, so it adds nothing here; baseline 3 is correct when the schema does all the work.

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?

Specific verb ('List') plus a precisely bounded resource (EuroComply commercial packs, emergency deal bundles, statutory workbooks) and the scope qualifier 'available for instant purchase via Polar.' An agent can tell this apart from get_pack_checkout_link or verify_pack_license, though it never names a sibling explicitly to route against.

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?

Usage is only implied: the agent infers this is the discovery/browse step before purchasing or verifying a pack. There is no explicit when-to-use statement, no exclusion, and no pointer to get_pack_checkout_link or verify_pack_license as the follow-up step, which would have been the natural pair for a catalog tool.

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