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

Annotations already mark the tool read-only, idempotent, and non-destructive. The description adds value by disclosing the output characteristic ('returns actuators with torque margin') and the fallback behavior when torque is missing. No contradiction with 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?

Two sentences, front-loaded with the purpose, with zero filler. The conditional is placed as the closing sentence. Efficient.

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?

Given no output schema, the description adequately describes the return (suitable actuators with torque margin, or typical variants). It covers the primary input conditions and the fallback. Minor gap: no mention of how results are formatted or whether filtering by voltage/flange is required, but these are in the schema. Complete enough for the tool's complexity.

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 80%, so the schema documents most parameters. The description adds cross-parameter guidance: diameter is the key fallback parameter when torque is unknown, and it clarifies that torque is optional in practice. This is meaningful but modest, so 4.

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 action ('подобрать привод' – select an actuator) and the exact resource class (electric/pneumatic actuators for valves, gates, and sluices) plus the selection criteria (DN, torque, ISO flange). This clearly distinguishes it from the broader product-search and recommendation siblings.

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 implies usage: when the user needs an actuator matched to a valve. It adds a conditional workflow (if torque unknown, provide DN only) which is guidance on how to use it. However, it does not explicitly exclude sibling tools or say when to prefer this over get_recommendations/suggest_accessories_for_cart, so it earns 4 rather than 5.

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