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

Annotations already declare readOnlyHint, idempotentHint and destructiveHint=false, so safety is covered. The description adds genuinely useful behavioral context beyond that: it is a static reference list (no parameters, no filtering), it covers B2C and B2B, some countries are 'on request', and prices come with volume discounts.

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 that leads with the resource and ends with the imperative 'read this before talking about prices'. The long parenthetical enumerations of seven filters and six countries add bulk but carry real content rather than 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?

With no output schema and no parameters, the description must convey what comes back, and it does: filter types, ready countries, price per 1,000 numbers, and volume discounts. It does not state currency, price format, or how 'on request' countries are handled, leaving minor gaps.

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?

The tool takes zero parameters, which is the baseline 4 case: there is nothing for the description to compensate for. The prose describes the catalog's dimensions (filters, countries) as fixed content rather than arguments, which is consistent with the empty 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 states a specific resource (live price list for Fresh DB fresh, filtered phone leads) and enumerates its contents, so an agent knows exactly what this returns. It does not explicitly contrast itself with the pricing-adjacent siblings get_quote or get_free_sample, so it falls short of a 5.

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?

'Read this before talking about prices' gives an explicit timing cue for use. However, with siblings get_quote and get_free_sample also touching pricing, the description never says when to prefer this catalog over a quote or a free sample, leaving the key routing decision to inference.

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