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

Annotations already cover the read-only/no-destructive/no-open-world profile, and the description layers on real operational context the annotations cannot: it is a demo with test payment and no charge, company search and emails are switched off, and the agent must never promise buyers. It also discloses locale fallback behavior. This is exactly the kind of beyond-schema behavior disclosure that earns a high score.

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?

The core purpose is front-loaded and each sentence carries policy or output information rather than filler. However, the 'order window' idea is repeated three times and the pricing-rule caveat is verbose, so it is slightly padded for a two-parameter read tool.

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 full burden of describing return content and does so thoroughly — plan names, USD prices, quotas, country limits, top-up rules, roles, stages, and segment/question mapping. Combined with the demo-state caveats, an agent has everything needed to call and interpret 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?

Schema description coverage is 100% for both parameters, and the description's statements about locale (uk, ru, en, fallback en) and hs_code (2-10 digits, picks the clarifying question and segments) largely restate the schema. Baseline 3 applies since the schema does the heavy lifting and the description adds little parameter-level syntax.

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 ('Read the buyer-search package offer') and enumerates the exact payload: plans with USD prices, company quotas, country limits, top-up rules, roles, order stages, and per-HS-code clarifying question plus segments. It explicitly distinguishes itself from the sibling get_subscription_plans, so an agent can route without opening either schema.

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?

Gives clear context ('Use it in the sales chat to answer questions and to suggest a plan and segments') and a firm behavioral boundary ('You only suggest: the person chooses and pays in the order window, never through you'). It also carves out the subscription-plans pricing rule. What's missing is an explicit when-not-to-use condition beyond that one contrast.

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