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

Annotations already declare readOnly, idempotent, non-destructive and closed-world (openWorldHint=false), and the description is consistent with that by framing this as a fixed ruble-priced catalog. It adds no further behavior detail such as result limits, pagination, or ranking, so it is only marginally beyond the annotations.

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?

A single front-loaded sentence opening with the verb and resource, zero filler. The trailing enumeration is effectively a catalog scope statement, though it is long enough to read as a list rather than a crisp clause.

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 should tell the agent what a result contains (names, prices, links, availability); it only implies titles/links via the lang parameter. Adequate for a read-only search but leaves the return shape to inference.

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% with all three parameters (lang, query, category) documented and an enum on lang, so the schema carries the parameter burden. The description adds scope context (ruble-priced digital goods) but no query syntax or category-slug guidance beyond the schema examples.

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?

Clear verb+resource ("Search Saikyo Shop digital goods") with a concrete enumeration of the catalog's contents (AI subscriptions, gift cards, game top-ups, Telegram Stars, software) and the payment currency (rubles). It does not explicitly contrast itself with siblings, but the domain is obviously distinct from the exchange-rate/AML/payment-passport tools.

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?

The description states what the tool searches but never says when to reach for it versus another tool, nor does it mention prerequisites or exclusions. An agent must infer usage purely from the domain wording.

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