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

With no annotations, the description carries the full behavioral disclosure burden. It discloses the data source (EGRUL) and the cost ($0.01 USDC), which is useful. It does not describe the response shape, potential failure modes, or any side effects beyond the paid lookup.

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 a single concise sentence with the core purpose front-loaded and a useful cost detail appended. Every word earns its place; there is no redundancy or filler.

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 simple one-parameter lookup, the description provides the resource and source, but it lacks parameter format guidance and does not hint at what the response contains, especially since no output schema is available. It is adequate but not fully self-sufficient.

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 0%, and the description only says 'по ИНН', which repeats the parameter name without adding format, validation, or example. Since this is for Russian legal entities, the expected 10-digit INN format should be stated; otherwise an agent may supply an invalid value.

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 and resource: 'Проверка российского юрлица по ИНН (ЕГРЮЛ)' — checking a Russian legal entity by INN using the EGRUL registry. This clearly distinguishes the tool from siblings like cbr_rates or pochta_offices.

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 gives clear context for when to use the tool: when an agent needs to verify a Russian legal entity by INN. However, it does not explicitly mention when not to use it or point to an alternative like company_report, so usage guidance is implied rather than explicit.

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