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

With no annotations at all, the description carries the full behavioral burden, yet it only implies a read via 'Карточка'. It says nothing about permissions, whether a missing SKU errors or returns empty, or rate limits. The trailing sentence about a shared store-section link is too vague to convey actionable behavior.

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 short sentences, front-loaded with the purpose and the parameter's origin. The second sentence earns little and reads as cryptic rather than informative, which is the only real efficiency loss.

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?

An output schema exists, so return values need not be explained, and the single-parameter surface is simple. What is missing is failure behaviour for an unknown SKU and any clarity on the 'shared link' remark, which leaves an agent guessing about edge cases.

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 coverage is 0% and product_id is bare 'string', so the description does real work by defining the value as the seller's exact article number sourced from search_products. It still gives no format or example, so it compensates only partially.

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 concrete verb+resource ('Карточка' / fetch the product card) and scopes it to an exact seller SKU, which implicitly separates it from the broader search_products sibling. It stops short of naming the sibling as the alternative route, but the resource and lookup key are unambiguous.

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?

'по точному артикулу продавца из search_products' tells the agent both the precondition (the ID must come from search_products) and the lookup mode (exact match, not fuzzy). No explicit when-not or fallback behaviour is given, so it is context without exclusions.

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