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

Annotations already provide readOnlyHint=true. The description adds non-obvious behavioral context: the tool depends on a separately connected MCP service and will return a refusal without it, and it defines the output granularity as one row per procurement object at OKPD2/KTRU level. This goes beyond the annotations without contradicting them.

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 description is compact but informative: it front-loads the core action, then gives row semantics, the use case, and the access prerequisite. Each sentence adds value, though the field enumeration makes it slightly longer than strictly necessary.

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?

For a 17-parameter read-only search tool with no output schema, the description provides a clear output field list, a use case, and an access disclaimer, while the schema covers all parameters. It does not describe the response envelope or pagination, but the includeTotal and pageSize parameter descriptions already cover the relevant behavior.

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%, and every parameter already has a meaningful description. The description provides output and usage context but does not need to add parameter-level semantics, so the baseline 3 applies.

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 verb and resource: 'Поиск по товарным позициям спецификаций заключённых контрактов'. It also defines the row granularity at OKPD2/KTRU level and enumerates the returned fields, which distinguishes it from the broader contract and specification search 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 explicitly gives the intended use case: 'кто, у кого и почём купил конкретный товар'. This is clear contextual guidance, though it does not name specific sibling tools or state when not to use it.

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